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单词 wood
释义

wood


wood

the hard, fibrous substance of a tree or shrub; the trunks or main stems of trees; timber or lumber: Most furniture is made out of wood.
Not to be confused with:would – past tense and past participle of will: Would you have gone to the game with me if I had asked you to?

wood 1

W0232200 (wo͝od)n.1. a. The secondary xylem of trees and shrubs, lying beneath the bark and consisting largely of cellulose and lignin.b. This tissue when cut and dried, used especially for building material and fuel.2. often woodsa. A growth of trees and other plants usually covering a smaller area than a forest.b. A forest.3. An object made of wood, especially:a. Music A woodwind.b. Sports Any of a series of golf clubs used to hit long shots, having a bulbous head made of wood, metal, or graphite, and numbered one to five in order of increasing loft.v. wood·ed, wood·ing, woods v.tr.1. To fuel with wood.2. To cover with trees; forest.v.intr. To gather or be supplied with wood.adj.1. Made or consisting of wood; wooden.2. Used or suitable for cutting, storing, or working with wood.3. woods Living, growing, or present in forests: woods animals; a woods path.Idiom: out of the woods Informal Free of a difficult or hazardous situation; in a position of safety or security.
[Middle English wode, from Old English wudu.]

wood 2

W0232200 (wo͝od)adj. Archaic Mentally deranged.
[Middle English, from Old English wōd; see wet- in Indo-European roots.]

wood

(wʊd) n1. (Botany) the hard fibrous substance consisting of xylem tissue that occurs beneath the bark in trees, shrubs, and similar plants. 2. (Building) the trunks of trees that have been cut and prepared for use as a building material3. (Forestry) the trunks of trees that have been cut and prepared for use as a building material4. (Botany) a collection of trees, shrubs, herbs, grasses, etc, usually dominated by one or a few species of tree: usually smaller than a forest: an oak wood. 5. (Forestry) fuel; firewood6. (Golf) golf a. a long-shafted club with a broad wooden or metal head, used for driving: numbered from 1 to 7 according to size, angle of face, etcb. (as modifier): a wood shot. 7. (Tennis) tennis squash badminton the frame of a racket: he hit a winning shot off the wood. 8. (Squash & Fives) tennis squash badminton the frame of a racket: he hit a winning shot off the wood. 9. (Badminton) tennis squash badminton the frame of a racket: he hit a winning shot off the wood. 10. (Bowls & Bowling) one of the biased wooden bowls used in the game of bowls11. (Instruments) music short for woodwind See also woods3 (Brewing) casks, barrels, etc, made of wood12. have the wood on have got the wood on informal Austral and NZ to have an advantage over13. out of the wood out of the woods clear of or safe from dangers or doubts: we're not out of the wood yet. 14. see the wood for the trees (used with a negative) to obtain a general view of a situation, problem, etc, without allowing details to cloud one's analysis: he can't see the wood for the trees. 15. (Forestry) (modifier) made of, used for, employing, or handling wood: a wood fire. 16. (Forestry) (modifier) dwelling in, concerning, or situated in a wood: a wood nymph. vb17. (Forestry) (tr) to plant a wood upon18. to supply or be supplied with fuel or firewood[Old English widu, wudu; related to Old High German witu, Old Norse vithr] ˈwoodless adj ˈwoodlessness n

wood

(wʊd) adjobsolete raging or raving like a maniac[Old English wōd; related to Old High German wuot (German Wut), Old Norse ōthr, Gothic wōths, Latin vātēs seer]

Wood

(wʊd) n1. (Biography) Mrs Henry, married name of Ellen Price. 1814–87, British novelist, noted esp for the melodramatic novel East Lynne (1861)2. (Biography) Sir Henry (Joseph). 1869–1944, English conductor, who founded the Promenade Concerts in London3. (Biography) John, known as the Elder. 1707–54, British architect and town planner, working mainly in Bath, where he designed the North and South Parades (1728) and the Circus (1754)4. (Biography) his son, John, known as the Younger. 1727–82, British architect: designed the Royal Crescent (1767–71) and the Assembly Rooms (1769–71), Bath5. (Biography) Ralph. 1715–72, British potter, working in Staffordshire, who made the first toby jug (1762)

wood1

(wʊd)
n. 1. the hard, fibrous substance composing most of the stem and branches of a tree or shrub, and lying beneath the bark; the xylem. 2. the trunks or main stems of trees as suitable for building and other purposes; timber or lumber. 3. firewood. 4. Often, woods. a large and thick collection of growing trees; a grove or forest. 5. a cask or keg, as distinguished from a bottle: aged in the wood. 6. any of a set of four golf clubs, orig. with wooden heads, used for hitting long shots. Compare iron (def. 5). adj. 7. made of wood; wooden. 8. used to store, work, or carry wood: a wood chisel. 9. dwelling or growing in woods: a wood bird. v.t. 10. to cover or plant with trees. v.i. 11. to take in or get supplies of wood (often fol. by up): to wood up before winter comes. Idioms: 1. knock on wood, (used when knocking on something wooden to assure continued good luck): The car's still in good shape, knock on wood. 2. out of the woods, no longer in a dangerous, critical, or difficult situation or condition; safe. [before 900; Middle English; Old English wudu, earlier widu, c. Old High German witu, Old Norse vithr; akin to Old Irish fid tree, Welsh gwŷdd trees]

wood2

(wʊd)

adj. Archaic. mad; insane. [before 900; Middle English; Old English wōd, c. Old Norse ōthr raging, Gothic wods possessed by demons]

Wood

(wʊd)

n. Grant, 1892–1942, U.S. painter.

wood

(wo͝od) The tough, fibrous substance lying beneath the bark of trees and shrubs, consisting of the vascular tissue known as xylem. The main components of wood are cellulose and lignin.

Wood

See also plants; trees
hylephobiaan intense dislike for wood.hylomaniaa mania for wood.joinerythe skill, craft, or trade of a joiner or carpenter; woodworking. — joiner, n.lignificationthe process of turning into wood or becoming woodlike.marquetrya form of decoration, often used in furniture-making, composed of inlays of wood veneers of different colors.parquetrymosaic work in wood, a form of marquetry, used mostly for floors and wainscoting.poker paintingxylopyrography.turnerythe process or craft of fashioning wood on a lathe.xylologya branch of dendrology that studies the structure of wood.xylomancya form of divination involving small pieces of wood.xylopyrographythe art or technique of producing a picture or design on a piece of wood by burning it with a heated, pointed instrument. Also called poker painting.

wood

1. 'wood'

Wood is the material which forms the trunks and branches of trees, and which is used to make things such as furniture.

He made a shelf out of a piece of wood.The wood of the window frames was all rotten.

Be Careful!
Don't refer to a piece of wood as 'a wood'.

2. 'wooden'

You don't usually use 'wood' in front of a noun to say that something is made of wood. Use wooden.

She kept their toys in a wooden box.They were all sitting at a long wooden table.

wood


Past participle: wooded
Gerund: wooding
Imperative
wood
wood
Present
I wood
you wood
he/she/it woods
we wood
you wood
they wood
Preterite
I wooded
you wooded
he/she/it wooded
we wooded
you wooded
they wooded
Present Continuous
I am wooding
you are wooding
he/she/it is wooding
we are wooding
you are wooding
they are wooding
Present Perfect
I have wooded
you have wooded
he/she/it has wooded
we have wooded
you have wooded
they have wooded
Past Continuous
I was wooding
you were wooding
he/she/it was wooding
we were wooding
you were wooding
they were wooding
Past Perfect
I had wooded
you had wooded
he/she/it had wooded
we had wooded
you had wooded
they had wooded
Future
I will wood
you will wood
he/she/it will wood
we will wood
you will wood
they will wood
Future Perfect
I will have wooded
you will have wooded
he/she/it will have wooded
we will have wooded
you will have wooded
they will have wooded
Future Continuous
I will be wooding
you will be wooding
he/she/it will be wooding
we will be wooding
you will be wooding
they will be wooding
Present Perfect Continuous
I have been wooding
you have been wooding
he/she/it has been wooding
we have been wooding
you have been wooding
they have been wooding
Future Perfect Continuous
I will have been wooding
you will have been wooding
he/she/it will have been wooding
we will have been wooding
you will have been wooding
they will have been wooding
Past Perfect Continuous
I had been wooding
you had been wooding
he/she/it had been wooding
we had been wooding
you had been wooding
they had been wooding
Conditional
I would wood
you would wood
he/she/it would wood
we would wood
you would wood
they would wood
Past Conditional
I would have wooded
you would have wooded
he/she/it would have wooded
we would have wooded
you would have wooded
they would have wooded

wood

Wooden club used for longer shots.
Thesaurus
Noun1.wood - the hard fibrous lignified substance under the bark of treesbeam - long thick piece of wood or metal or concrete, etc., used in constructionbentwood - wood that is steamed until it becomes pliable and then is shaped for use in making furniture; "bentwood chairs"chopping block - a steady wooden block on which food can be cut or diced or wood can be splitspindle - a piece of wood that has been turned on a lathe; used as a baluster, chair leg, etc.pine - straight-grained durable and often resinous white to yellowish timber of any of numerous trees of the genus Pinuslarch - wood of a larch treefir - nonresinous wood of a fir treecedarwood, cedar - durable aromatic wood of any of numerous cedar trees; especially wood of the red cedar often used for cedar chestsspruce - light soft moderately strong wood of spruce trees; used especially for timbers and millworkhemlock - soft coarse splintery wood of a hemlock tree especially the western hemlockcypress - wood of any of various cypress trees especially of the genus Cupressusredwood - the soft reddish wood of either of two species of sequoia treessandarac, citronwood - durable fragrant wood; used in building (as in the roof of the cathedral at Cordova, Spain)kauri - white close-grained wood of a tree of the genus Agathis especially Agathis australisyellowwood - the yellow wood of any of various yellowwood treesyew - wood of a yew; especially the durable fine-grained light brown or red wood of the English yew valued for cabinetwork and archery bowslancewood - durable straight-grained wood of the lacewood tree; used for building and cabinetwork and toolstrue tulipwood, whitewood, yellow poplar, tulipwood, white poplar - light easily worked wood of a tulip tree; used for furniture and veneerzebrawood - handsomely striped or mottled wood of the zebrawood tree; used especially for cabinetworkcocoswood, cocuswood, granadilla wood - wood of the granadilla tree used for making musical instruments especially clarinetsshittimwood - wood of the shittah tree used to make the ark of the Hebrew Tabernaclesabicu, sabicu wood - the wood of the sabicu which resembles mahoganybamboo - the hard woody stems of bamboo plants; used in construction and crafts and fishing polestulipwood - the variegated or showily striped ornamental wood of various tulipwood treesbalsa, balsa wood - strong lightweight wood of the balsa tree used especially for floatssilver quandong - pale easily worked timber from the quandong treeobeche - the wood of an African obeche tree; used especially for veneeringbasswood, linden - soft light-colored wood of any of various linden trees; used in making crates and boxes and in carving and millworkbeefwood - any of several heavy hard reddish chiefly tropical woods of the families Casuarinaceae and Proteaceae; some used for cabinetworkbriarwood, brierwood, brier-wood - wood from the hard woody root of the briar Erica arborea; used to make tobacco pipesbeechwood, beech - wood of any of various beech trees; used for flooring and containers and plywood and tool handleschestnut - wood of any of various chestnut trees of the genus Castaneaoak - the hard durable wood of any oak; used especially for furniture and flooringbirch - hard close-grained wood of any of various birch trees; used especially in furniture and interior finishes and plywoodalder - wood of any of various alder trees; resistant to underwater rot; used for bridges etchazel - the fine-grained wood of a hazelnut tree (genus Corylus) and the hazel tree (Australian genus Pomaderris)olive - hard yellow often variegated wood of an olive tree; used in cabinetworkash - strong elastic wood of any of various ash trees; used for furniture and tool handles and sporting goods such as baseball batsironwood - exceptionally tough or hard wood of any of a number of ironwood treeswalnut - hard dark-brown wood of any of various walnut trees; used especially for furniture and panelinghickory - valuable tough heavy hardwood from various hickory treespecan - wood of a pecan treepyinma - relatively hard durable timber from the Queen's crape myrtle; light reddish brown, smooth and lustrousgumwood, gum - wood or lumber from any of various gum trees especially the sweet gumeucalyptus - wood of any of various eucalyptus trees valued as timbertupelo - pale soft wood of a tupelo tree especially the water gumpoon - wood of any poon tree; used for masts and sparsred lauan - hard heavy red wood of the red lauan tree; often sold as Philippine mahoganyelmwood, elm - hard tough wood of an elm tree; used for e.g. implements and furniture
2.wood - the trees and other plants in a large densely wooded areawood - the trees and other plants in a large densely wooded areaforest, woodsbotany, flora, vegetation - all the plant life in a particular region or period; "Pleistocene vegetation"; "the flora of southern California"; "the botany of China"bosk - a small wooded areagrove - a small growth of trees without underbrushjungle - an impenetrable equatorial forestrain forest, rainforest - a forest with heavy annual rainfallunderbrush, undergrowth, underwood - the brush (small trees and bushes and ferns etc.) growing beneath taller trees in a wood or foresttree - a tall perennial woody plant having a main trunk and branches forming a distinct elevated crown; includes both gymnosperms and angiospermsold growth, virgin forest - forest or woodland having a mature or overly mature ecosystem more or less uninfluenced by human activitysecond growth - a second growth of trees covering an area where the original stand was destroyed by fire or cutting
3.Wood - United States film actress (1938-1981)Natalie Wood
4.wood - English conductor (1869-1944)Wood - English conductor (1869-1944) Sir Henry Joseph Wood, Sir Henry Wood
5.Wood - English writer of novels about murders and thefts and forgeries (1814-1887)Ellen Price Wood, Mrs. Henry Wood
6.wood - United States painter noted for works based on life in the Midwest (1892-1942)Wood - United States painter noted for works based on life in the Midwest (1892-1942)Grant Wood
7.wood - any wind instrument other than the brass instrumentswood - any wind instrument other than the brass instrumentswoodwind, woodwind instrumentbeating-reed instrument, reed instrument, reed - a musical instrument that sounds by means of a vibrating reedfinger hole - one of a series of holes in a woodwind instrument; pitch changes when a finger covers itflute, transverse flute - a high-pitched woodwind instrument; a slender tube closed at one end with finger holes on one end and an opening near the closed end across which the breath is blownthumbhole - the hole in a woodwind that is closed and opened with the thumbwind instrument, wind - a musical instrument in which the sound is produced by an enclosed column of air that is moved by the breath
8.wood - a golf club with a long shaft used to hit long shots; originally made with a wooden head; "metal woods are now standard"brassie - (formerly) a golfing wood with a face more elevated that a driver but less than a spoonnumber one wood, driver - a golf club (a wood) with a near vertical face that is used for hitting long shots from the teegolf-club, golf club, club - golf equipment used by a golfer to hit a golf ballmetal wood - golf wood with a metal head instead of the traditional wooden headspoon - formerly a golfing wood with an elevated face

wood

noun1. timber, planks, planking, lumber (U.S.) The floor is made of polished wood.2. woods woodland, trees, forest, grove, hurst (archaic), thicket, copse, coppice After dinner they went for a walk through the wood.3. firewood, fuel, logs, kindling We gathered wood for the fire.out of the wood(s) safe (usually used in a negative construction) clear, secure, in the clear, out of danger, home and dry (Brit. slang), safe and sound The nation's economy is not out of the woods yet.Related words
adjectives ligneous, sylvan, xyloid
like hylomania

Types of wood

African mahogany, afrormosia, alerce, amboyna or amboina, apple, ash, assegai or assagai, balsa, basswood, baywood, beech, beefwood, birch, black walnut, bog oak, boxwood, brazil, brasil, or brazil wood, bulletwood, butternut, cade, calamander, camwood, candlewood, cedar, cherry, chestnut, citron wood, coachwood, corkwood, crabwood, cypress, durmast or durmast oak, eaglewood, ebony, elm, fiddlewood, fir, gaboon, gopher wood, greenheart, guaiacum or guaiocum, gumtree or gumwood, hackberry, hardwood, hazel, hemlock, hickory, hornbeam, iroko, ironwood, jacaranda, jelutong, kauri, kiaat, kingwood, koa, lancewood, larch, locust, mahogany, maple, marblewood, nutwood, oak, olive, orangewood, padauk or padouk, Paraná pine, partridge-wood, pear, persimmon, pine, pitch pine, poon, poplar, pulpwood, quassia, quebracho, red cedar, red fir, red gum, red oak, ribbonwood, rosewood, sandalwood, sandarac, sappanwood, sassy, sasswood, or sassy wood, satinwood, Scots pine, shagbark or shellbark, sneezewood, softwood, spotted gum, spruce, stinkwood, sumach or sumac (U.S.), sycamore, tamarack, tamarind, teak, thorn, toon, torchwood, tulipwood, tupelo, walnut, western red cedar, white cedar, white pine, whitewood, willow, yellowwood, yew, zebrawood
Translations
木材树林小树林打高尔夫球的木制球棒木头

wood

(wud) noun1. (also adjective) (of) the material of which the trunk and branches of trees are composed. My desk is (made of) wood; She gathered some wood for the fire; I like the smell of a wood fire. 木頭,木材 木头,木材 2. (often in plural) a group of growing trees. They went for a walk in the woods. 樹林 树林3. a golf-club whose head is made of wood. 木製高爾夫球棒 打高尔夫球的木制球棒ˈwooded adjective (of land) covered with trees. a wooded hillside. 長滿樹木的 长满树木的ˈwooden adjective made of wood. three wooden chairs. 木製的 木制的ˈwoody adjective1. covered with trees. woody countryside. 樹木遍佈的 树木茂密的2. (of a smell etc) of or like wood. 木頭(般)的(氣味) 木头味ˈwood carving noun the art of carving wood. 木雕 木雕ˈwoodcut noun a print made by pressing a block of wood with design cut on it onto paper. 木刻版畫 木刻,木刻画 ˈwoodcutter noun a person whose job is felling trees. 伐木工 伐木工人ˈwoodland noun land covered with woods. a stretch of woodland. 林地 林地(林区) ˈwoodlouseplural ˈwoodlice noun a tiny creature with a jointed shell, found under stones etc. 潮蟲 土鳖ˈwoodpecker noun a type of bird which pecks holes in the bark of trees, searching for insects. 啄木鳥 啄木鸟ˈwood pulp noun pulp from wood that can be used for making paper. (用以造紙的)木漿 木质纸浆ˈwoodwind (-wind) noun (in an orchestra, the group of people who play) wind instruments made of wood. 木管樂器 木管乐器ˈwoodwork noun1. the art of making things from wood; carpentry. He did woodwork at school. 木製品 木制品2. the wooden part of any structure. The woodwork in the house is rotting. 結構的木工部份 建筑中的木工活ˈwoodwormplurals ˈwoodworm, ~woodworms noun the larva of a certain type of beetle, which bores into wood and destroys it. 蛀蟲 蛀虫out of the wood(s) out of danger. 脫離險境 脱离险境

wood

小树林zhCN, 木材zhCN

wood


wood

verbSee peckerwood
See:
  • a babe in the woods
  • babe in the woods
  • babe(s) in the woods
  • babes in the wood
  • be (not) out of the woods
  • cannot see the wood for the trees
  • can't see the forest for the trees
  • can't see the forest/wood(s) for the trees
  • can't see the wood for the trees
  • cut the deadwood out
  • dead wood
  • deadwood
  • Do bears crap in the woods?
  • Do bears poop in the woods?
  • Does a bear crap in the woods?
  • Does a bear poop in the woods?
  • don't halloo before you are out of the woods
  • don't halloo till you are out of the woods
  • don't halloo until you are out of the woods
  • don't whistle before you are out of the woods
  • don't whistle till you are out of the woods
  • don't whistle until you are out of the woods
  • Fields have eyes, and woods have ears
  • have the wood on
  • have the wood on (someone or something)
  • hewers of wood and drawers of water
  • I wasn't brought up in the woods to be scared by owls
  • in (one's) neck of the woods
  • in some neck of the woods
  • in this/that neck of the woods
  • in your, this, etc. neck of the woods
  • knock on wood
  • knock wood
  • morning wood
  • neck of the woods
  • neck of the woods, this
  • never halloo before you are out of the woods
  • Never halloo till you are out of the woods
  • never halloo until you are out of the woods
  • never whistle before you are out of the woods
  • never whistle till you are out of the woods
  • never whistle until you are out of the woods
  • not able to see the wood for the trees
  • not out of the wood
  • not out of the woods
  • not see the wood for the trees
  • not set the woods on fire
  • out of the wood
  • out of the wood(s)
  • out of the woods
  • peckerwood
  • saw wood
  • set the woods on fire
  • the woods are full of (someone or something)
  • the woods are full of something
  • touch wood
  • wood
  • wood butcher
  • wood-pussy
  • woods are full of
  • your neck of the woods

Wood


wood,

botanically, the xylem tissue that forms the bulk of the stem of a woody plant. Xylem conducts sap upward from the roots to the leaves, stores food in the form of complex carbohydrates, and provides support; it is made up of various types of cells specialized for each of these purposes. Among them are tracheids, elongated conduction and support cells; parenchyma (food storage) cells, some of which form rays for transverse conduction; xylem vessels, formed of hollow cells joined end to end; and fiber cells that reinforce these tubes. In the conifers the xylem is made up mainly of tracheids, thus presenting a uniform, nonporous appearance; their wood is called softwood. Deciduous trees have more complex xylem, permeated by vessels, and are called hardwoods, although the description is sometimes inaccurate.

The xylem is formed in the growing season by the cambiumcambium
, thin layer of generative tissue lying between the bark and the wood of a stem, most active in woody plants. The cambium produces new layers of phloem on the outside and of xylem (wood) on the inside, thus increasing the diameter of the stem.
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; in temperate regions the cells formed in the spring are larger in diameter than those formed in the summer, and this results in the annual rings observable in cross section. The new cells lose their protoplasm as they form the various tissues; the older, nonfunctional cells become plugged up, darken in color, and often accumulate bitter or poisonous substances (tannins, dyes, resins, and gums). This inner wood (the heartwood, as opposed to the functional sapwood) is valued for outdoor construction because of its resistance to moisture and to decay-producing organisms.

Commercial Uses

Freshly cut wood contains much moisture and tends to warp and split as it dries. Lumber is therefore seasoned before use—dried either slowly in the sun and air or more quickly by artificial means (kiln drying). Seasoning increases wood's buoyancy, strength, elasticity, and durability. Although synthetic materials have supplanted wood in many of its former uses, it is still widely employed for furniture, floors, railway ties, paper manufacture, and innumerable other purposes. Wood distillation yields methyl alcohol, wood tar, acetic acid, acetone, and turpentine; charcoal is made by burning or heating wood in insufficient air to consume it.

The wood of different species of trees varies considerably in weight, strength, and appearance. Softwood is normally uniform in grain (texture) and color; hardwood, in which the rays are more prominent and the arrangement of tissues is variable, produces lumber in which the grain may run vertically or horizontally and be coarse or smooth. The manner in which a log is cut results in lumber with thin or wide ray markings. A log cut horizontally shows the concentric annual rings; lengthwise cuts through the center are marked by thin vertical ray lines; and lengthwise cuts through the outer sections show the wood's characteristic wavy grain and wider ray markings, prized for their beauty. The rarer decorative woods may be cut in thin layers and glued to other wood structures (see veneerveneer
, thin leaf of wood applied with glue to a panel or frame of solid wood. The art of veneer developed with early civilization. It produces richly grained effects cheaply and is used also on structural parts that must be cut with the grain for strength.
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). Plywoodplywood,
manufactured board composed of an odd number of thin sheets of wood glued together under pressure with grains of the successive layers at right angles. Laminated wood differs from plywood in that the grains of its sheets are parallel.
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, made of thin layers of wood glued so that the grains alternate in direction, makes an especially strong construction material. For some applications composition boardcomposition board,
wood product produced in the form of a board or sheet, formed of cellulose fibers or particles derived from wood or other sources, and used principally as a building material.
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 offers another inexpensive substitute. The more recently developed cross-laminated timbercross-laminated timber
(CLT), manufactured wood panels that consist of layers of boards glued together under pressure with the grain of the boards in one layer running perpendicular to the grain in adjoining layers.
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 is used to prefabricate entire walls or large sections of ceiling and floor. Pressure-treated woodpressure-treated wood,
wood that has had a liquid preservative forced into it in order to protect against deterioration due to rot or insect attack. The most commonly used preservatives are chromated copper arsenate (CCA) and pentachlorophenol.
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 is lumber that has had a preservative forced into it under pressure.

Bibliography

See H. Cone, Wood Structure and Identification (1979); H. Bucksh, Dictionary of Wood and Woodworking Practice (2 vol., 1986).

Wood

The hard, fibrous substance that composes the trunk and branches of a tree, lying between the pitch and the bark.

artificial wood

Any of the various mixtures that are molded to simulate wood; often using sawdust, paper, or other wood fiber as a major ingredient mixed with glue.

bald cypress

A deciduous softwood tree resistant to decay and often used in contact with the soil and for exposed elements such as wood shingles; also used for flooring and trim.

balsam fir

A softwood tree with coarse-grained wood, used for interior trim.

balsam poplar

A large hardwood tree, with soft straight-grained wood used for painted millwork.

bevel siding

Tapered boards used as siding, installed with the thinner part at the top.

birch

A moderately strong, high-density wood, yellowish to brown in color; its uniform texture is well suited for veneer, flooring, and turned wood products.

burl

A decorative pattern in wood caused by adjacent knots.

cedar

A highly aromatic, moderately high-density, fine-textured wood of a distinctive red color with white streaks; widely used for fence posts, shingles, and mothproof closet linings.

cherry

An even-textured, moderately high-density wood, rich red-brown in color; takes a high luster, and is used for cabinetwork and paneling.

chestnut

A light, coarse-grained, medium-hard wood, used for ornamental work and trim.

clapboard

One of a series of boards used for siding, with a tapered cross section, most commonly called beveled siding.

clapboard siding

A wood siding commonly used as an exterior covering on a building of frame construction, applied horizontally and overlapped, with the grain running lengthwise, thicker along the lower edge than the upper.

conifer

A tree belonging to the botanical group which bears cones; it includes all the softwoods used in building, particularly the pines and firs.

cypress

A moderately strong, hard, and heavy softwood; its heartwood is naturally decay-resistant, and is used for exterior and interior construction where durability is required.

dimensional timber

Rough-sawn wood with a rectangular or square cross section that exceeds the nominal dimensions of 4 by 5 inches.

Wood

 

in art. Since ancient times wood has been used in architecture, sculpture, and decorative applied art, especially folk art, including such applications as utensils and furniture, often stained or decorated with carvings, intarsia, paintings, or gilding; carvings on the facades and interiors of buildings; and the facing of walls with laths or planks. Wood has also been used in the preparation of forms for woodcuts, printed cloth, and cookies. The wealth of color nuance in wood and the diversity in its texture and graining—its waviness, concentricity, and the pictorial interweaving of its fibers—makes possible a multitude of decorative effects, while the relative ease with which wood can be worked enables the artist to express his creative energy with greater spontaneity.

REFERENCE

Dvoinikova, E. S., and I. V. Liamin. Khudozhestvennaia obrabotka dereva. Moscow, 1958.

Wood

 

xylem, the complex tissue of arboreal and herbaceous plants that conducts water and dissolved mineral salts within the plant. Wood is the part of the conducting bundle that is formed from the procambium, or primary xylem, and the cambium, or secondary xylem. It forms the major portion of the trunk, roots, and branches of arboreal plants.

Physiological and anatomical properties. The form and size of the cells that make up wood vary and depend on their function. Wood contains conductive, mechanical, and storage elements. The structure of wood is specific to genera and sometimes to species of arboreal plants. Basically three sections or microscopic sections are used in studying wood and its properties: the cross section, the tangential section, and the radial section (see Figure 1). As the tree grows, the internal older wood of the trunk dies. The conductive elements

Figure 1. Main parts of the trunk and chief sections: (1) cross section, (2) radial section, (3) tangential section

gradually become clogged—the vessels, with so-called tyloses, and the tracheids, with tori of their bordered pits. The conductive and storage systems cease to function and the wood’s content of water, starch, and oils decreases. The amount of resin and tannic substances increases. In heart-wood varieties, such as pine, larch, and oak, the central part of the wood differs in color and is called the heartwood; the outer zone is called the sapwood. In ripe arboreal varieties (such as spruce and linden) the outer part differs from the center in that it has less moisture. This type of wood is called mature. Sapwood varieties, such as maple and birch, show no distinction between the central and the peripheral parts. Sometimes the trunks of sapwood and ripe arboreal varieties have darker centers (usually the effect of fungi), forming so-called false heartwood.

The wood of most dicotyledonous and all coniferous plants shows growth rings, or annual rings, and wood rays, or medullary rays. Within a single growth ring, early (springwood) and late (summerwood) zones can be discerned. The wood rays carry nourishment to places of deposit. The dimensions of the elements making up the wood and the relationships between them vary, depending on growth conditions and the location of the wood in the stem. With unfavorable conditions (a surplus of moisture or insufficient soil water, heavy shade, or leaf damage by insects), the growth layers are thin. The wood of dicotyledonous plants is composed of cells of the following types of tissue: vessel elements (tracheae), tracheids, mechanical fibers (libri-form), wood parenchyma, and a number of other (transitional) elements (see Figure 2). Combinations in the size and

Figure 2. Types of cells in wood: (a) xylem parenchyma, (b) tracheids, (c) vessel elements (tracheae), (d) libriform fibers, (e) cells of heterogeneous medullary ray in conifer, (f) cells of heterogeneous medullary ray in deciduous tree

distribution of these elements (for example, the diameter of the vessels of different varieties ranges from 0.0015 mm in box and aralia to 0.5 mm in oak) create the diversity of wood structure (see Figure 3). In diffuse-porous varieties, vessels of almost equal diameter are found throughout the growth ring, and their number in the early and late zones are approximately the same (as in birch and maple), whereas ring-porous varieties have considerably larger vessels in the early growth zone than in the late (as in oak, elm, and osage orange). Vessels may be found individually (in oaks) or arranged in clusters (in ashes, birches, and aspens); in the latter case, bordered pits are formed at the points of contact, and in the process of evolution the tracheids lose the function of water conduction and are replaced by libriform fibers. For example, ash wood is composed of vessels, xylem parenchyma and radial parenchyma, and libriform fibers.

Figure 3. Diagram of vessel arrangement in cross section of an annual ring: (1) maple (diffuse-porous), (2) elm (ring-porous)

Woods also differ in the nature of the union between vessel elements, the type and distribution of perforation (simple, staircased), the shape of the elements, and the height and breadth of the medullary ray and the shape of its cells. Gymnosperms, including conifers, contain only tracheids (vessels are absent), a small amount of xylem parenchyma, and medullary rays. Some genera, such as cypress and juniper, have homogeneous medullary rays of identical parenchymal cells. In others, including pine, spruce, and larch, the rays are heterogeneous and contain ray tracheids which run along the main ray (see Figure 4). The structure of the ray, the shape of the cells, and the number and size of the pits are very important factors in determining the variety. In some genera (pine, spruce, Douglas fir, and larch), the wood has resin canals.

Chemical composition. Absolutely dry wood of all varieties contains, on the average, 49.5 percent carbon, 6.3 percent hydrogen, 44.1 percent oxygen, and 0.1 percent nitrogen. The cell walls account for about 95 percent of the weight of the wood. The chief components of the cell wall are cellulose (43-56 percent) and lignin (19-30 percent); its other component substances include hemicelluloses, pectins, minerals (mainly calcium salts), a small amount of oils, essential oils, alkaloids, and glycosides. Lignification—that is, impregnation of the cell walls with lignin—is characteristic of all wood cells. There are more than 70 lignification reactions (for example, phloroglucinol with concentrated hydrochloric acid, which imparts a raspberry coloration). The wood of some trees contains tannins (quebracho), dyes (logwood and sandal), balsams, resins, and camphor.

O. N. CHISTIAKOVA

Physical properties. The physical properties of wood are characterized by outward appearance (color, luster, and texture), density, moisture content, hygroscopicity, and heat capacity. As a material, wood is used both in its natural form (as timber and lumber) and after special physical and chemical treatment. An important decorative property and diagnostic sign is the color of the wood, which varies within broad boundaries (hue, from 578 to 585 nanometers; color purity, from 30 to 60 percent; and brightness, from 20 to 70 percent). The luster of wood is best observed in certain deciduous varieties, particularly in a radial section. The texture and figure of wood formed by cutting across anatomical elements are especially striking in deciduous varieties.

Wood contains both free moisture (in the cell cavities) and bound moisture (in the cell walls). The moisture content of wood is determined by the formula Wood,where W is the water content in percentage, m is the initial weight of the specimen, and m0 is the weight of the specimen when absolutely dry. The hygroscopic limit (saturation point of fibers) is the point at which the wood contains a maximum of bound (hygroscopic) moisture and no free moisture. The moisture content corresponding to the hygroscopic limit Wh1, at a temperature of 20°C amounts on the average to 30 per-cent. Most properties of wood are affected by changes in the bound moisture content. When seasoned long enough, wood acquires an equilibrium moisture We, which is a function of the moisture ø and the temperature of the surrounding air t

Figure 4. Portions of pinewood sections: (1) cross section, (2) radial section, (3) tangential section; (a) edge ot annual ring, (b) summerwood, (c) springwood, (d) new series of tracheids, (e) heterogeneous medullary ray composed of ray tracheids (f) with small bordered pits, and (g) composed of parenchyma cells with large windowlike pits, (h) resin canal (epithelial cells lining it clearly visible), (i) cells of parenchyma surrounding resin canal, (j) bordered pits, (k) medullary ray with horizontal resin canal

(see Figure 5). Lowering the bound moisture content shortens the linear dimensions and volume of the wood. This is called shrinkage. Wood shrinkage is determined by the formula Woodwhere Sw is the shrinkage in percentage, ahl is the size (volume) of the sample at the hygroscopic limit, and aw is the size (volume) of the sample at moisture content W within the range 0-Whl. Absolute shrinkage (the removal of all bound water) in a tangential direction for all varieties is 6-10 percent; in a radial direction, 3-5 percent; along the grain, 0.1–0.3 percent; and in three dimensions, 12-15 percent.

Figure 5. Equilibrium moisture of wood W, as a function of moisture ø and air temperature t

Increasing the bound moisture content and the absorption of other liquids causes swelling, the opposite of shrinkage. The difference in the values of radial and tangential shrinkage in seasoning (or soaking) causes transverse warping of lumber and unseasoned stock. Longitudinal warping is most noticeable in lumber with structural faults. Because moisture is removed unevenly in the drying process and because of anisotropy, internal tensions develop that lead to the splitting of lumber and round timber. Because certain stresses remain in the wood after mechanical treatment, it is kiln dried to change the dimensions and form of lumber pieces. Wood is permeable to fluids and gases; this is especially true of the sapwood and the longitudinal fibers of deciduous varieties.

The density of the woody substance in all varieties is the same (since the chemical composition is the same)—roughly 1.5 times the density of water. Because of the presence of cavities, the density of wood itself is less and varies within broad limits, depending on the variety, the growth conditions, and the position of the sample in the trunk. The density of wood at a given moisture content pw = mw/vw, where mw and vw are the weight and volume of the specimen at given moisture content W. With increases in moisture content, the density of the wood increases. Frequently an index that is independent of moisture content is used to calculate density: relative density ρr = m0/vmax, where m0 is the weight of the sample at W = 0 and vmax is the volume at W > Wh1.

The specific heat of wood is practically independent of variety and can be diagramed (see Figure 6). The coefficient of

Figure 6. Specific heat C of wood as a function of temperature t and moisture W

thermal conductivity λ is a function of the temperature, moisture content, and variety (density), in addition to the direction of the heat flow, according to the formula λ. = λnomλ × kp × kx, where λnom is the nominal value of the coefficient of thermal conductivity, and kp and kx are coefficients for the value of the relative density pr and the direction of the heat flow in the sample. Values of λnom can be diagramed (see Figure 7); some values for the coefficients kp and kx are found

Figure 7. Coefficient of thermal conductivity of wood λnom as a function of temperature f and moisture W

in Table 1 and Table 2. Thermal strain in wood is significantly less than the strains of shrinking or swelling and usually is not used in calculations.

Table 1. Coefficient kx
Direction of heat flowkx
Tangential............1.0
Radial............1.05
Longitudinal ring-porous deciduous varieties............1.6
others............2.2
Table 2. Coefficient kp
pr,kg/m3kp
3400.98
3601.00
4001.05
5001.22
6001.56
6001.56
6501.86

Certain electric and acoustic properties of wood are presented in Table 3. Low density conifer woods (such as spruce) are highly resonant and are widely used in the manufacture of musical instruments.

Mechanical properties. The mechanical strength of wood is greatest when force is exerted along the grain; when it is exerted across the grain, the strength decreases sharply. Table 4 shows the average values for indexes of the properties of various woods at W = 12 percent. With increases in moisture to Whl, these figures decrease by 1.5-2 times. The modulus of elasticity of the fibers is 10-15 giganewtons per sq m (100,000-150,000 kilograms-force per sq cm) longitudinally; across the fibers, it is 20-25 times less. Poisson’s ratio for various types of wood and structural directions ranges from 0.02 to 0.8.

The capacity of woods to bend under weight over a period of time, which characterizes their rheological properties, rises sharply with increases in moisture and temperature. Toughness decreases under prolonged stress. For example, the limit of long-term resistance in bending is 0.6-0.65 of the limit of strength during standard testing for static flexion. With frequent loadings, wood undergoes fatigue; on the average, the limit of endurance in bending is two-tenths of the static limit of strength.

Wood is tested to determine the indexes of its physical, mechanical, and technological properties by using small flawless samples. A series of samples is tested, and the test results are evaluated using the methods of variation statistics. All measurements are taken at a moisture content of 12 percent. For most methods of testing, standards are worked out for the shape and size of the samples, the experimental procedures, and the means of calculating the property indexes. Wood is distinguished by sharp variability of its properties; therefore, the use of nondestructive methods for item-by-item testing of the strength of sawn lumber—based on such factors as the relation between the strength of wood and certain of its physical properties—is of particular importance when wood is being used as a structural material. The properties of wood are affected by defects such as knots, rot, fiber deviations, and pitch.

In evaluating its properties as a structural and craft material, the wood’s ability to hold metal fasteners (nails and screws), its strength, and its flexibility (in certain deciduous varieties) are taken into account.

Table 3. Electric and acoustic properties of wood
 Across fibers
IndexesVarietyAlong fibersRadiallyTangentially
Specific volume electric resistance at W = 8%, 108 ohm-mLarch3.81914.5
 Birch4.286
Breakdown voltage at W = 8-9%, kV/cmBeech
Birch
14
15
41.5
59.8
52
Dielectric constant at W = 0; 1,000 HzSpruce
Beech
3.06
3.18
1.91
2.40
1.91
2.20
Loss tangentSpruce
Beech
0.0625
0.0585
0.0310
0.0319
0.0345
0.0298
Velocity of propagation of sound, m/secPine
Oak
5,030
4,175
1,450
1,665
850
1,400

The quality coefficient of wood (the ratio of the limit of strength to density) is high; it resists blows and vibrations well; it is readily worked and can be made into objects of complex shapes; it joins reliably to make handicrafts and structural elements that require gluing; and its decorative properties are great. However, along with the positive features, natural wood has a number of shortcomings. For example, its size and shape vary with fluctuations in moisture, and it decays when poorly preserved or maintained (for example, under conditions of high humidity, moderately high air temperature, contact with wet soil, and condensation of moisture). Decay is a process of decomposition, the result of the vital activities of fungi that infest the wood. To protect against decay, wood is saturated with antiseptics. Wood can also be damaged by insects. This damage can be prevented by using insecticides. Because of its relatively poor fire resistance, wood must often be treated with antipyretic agents.

Economic significance. As a structural material, wood is used extensively in construction and cabinetry, railroad and communication lines (for the poles and sleepers of electric transmission lines), in mining (for timbering), in machine building and shipbuilding, and in the manufacture of furniture, musical instruments, and sports equipment. Wood is the raw material for the pulp and paper industries and for other types of chemical processing, such as hydrolysis and dry distillation. It also serves as a fuel.

Table 4. Density and mechanical properties of small flawless samples of wood at 12 percent moisture content
VarietyIndexesLarchPinespruceOakBirchAspen
Density, kg/m3............660500445690630495
Strength limit along fibers, MN/m2 (kgf/cm2) under compression64.5(645)46.5(485)44.5(445)57.5(575)55.0(550)42.5(425)
under static flexion111.5(1,115)86.0(860)79.5(795)107.5(1,075)109.5(1,095)78.0(780)
under tension125.0(1,250)103.5(1,035)103.0(1,030)168.0(1,680)125.5(1,255)
under shearing radial9.9(99)7.5(75)6.9(69)10.2(102)9.9(93)6.3(63)
tangential..............9.4(94)7.3(73)6.8(68)12.2(122)11.2(112)8.6(86)
Resilience, kJ/m2 (kgf-m/cm2)52(0.53)41(0.42)39(0.40)77(0.78)93(0.95)84(0.86)
Hardness, MN/m2 (kgf/cm2) face..............43.5(435)28.0(285)26.0(260)67.5(675)46.5(465)26.5(265)
side..............29.0(290)24.0(245)18.0(180)52.5(525)35.0(350)20.0(200)

REFERENCES

Vanin, S. I. Drevesinovedenie, 3rd ed. Moscow-Leningrad, 1949.
latsenko-Khmelevskii, A. A. Osnovy i melody anatomicheskikh issledovanii drevesiny. Moscow-Leningrad, 1954.
Moskaleva, V. E. Stroenie drevesiny i ee izmenenie prifizicheskikh i mekhanicheskikh vozdeistviiakh. Moscow, 1957.
Vikhrov, V. E. Diagnosticheskie priznaki drevesiny glavneishikh lesokhoziaistvennykh i lesopromyshlennykh porod SSSR. Moscow, 1959.
Nikitin, N. I. Khimiia drevesiny i tselliulozy. Moscow-Leningrad, 1962.
Drevesina: Pokazateli fiziko-mekhanicheskikh svoistv. Moscow, 1962.
Ugolev, B. N. Ispytaniia drevesiny i drevesnykh materialov. Moscow, 1965.
Perelygin, L. M. Drevesinovedenie, 2nd ed. Moscow, 1969.
Leont’ev, N. L. Tekhnika ispytanii drevesiny. Moscow, 1970.
Ugolev, B. N. Deformativnost’ drevesiny i napriazheniia pri sushke. Moscow, 197 .

B. N. UGOLEV

What does it mean when you dream about wood?

Wood is a traditional source of heat and is one of the five elements used in clinical diagnosis in Chinese medicine. Wood also represents life and springtime.

wood

[wu̇d] (botany) The hard fibrous substance that makes up the trunks and large branches of trees beneath the bark. (ecology) A dense growth of trees, more extensive than a grove and smaller than a forest. (materials) Lumber or timber obtained from trees.

wood

The hard fibrous substance which composes the trunk and branches of a tree, lying between the pith and bark.

wood

knocking on it averts dire consequences. [Western Culture: Misc.]See: Protection

wood

1. the hard fibrous substance consisting of xylem tissue that occurs beneath the bark in trees, shrubs, and similar plants 2. the trunks of trees that have been cut and prepared for use as a building material 3. a collection of trees, shrubs, herbs, grasses, etc., usually dominated by one or a few species of tree: usually smaller than a forest 4. fuel; firewood 5. Golfa. a long-shafted club with a broad wooden or metal head, used for driving: numbered from 1 to 7 according to size, angle of face, etc. b. (as modifier): a wood shot 6. Tennis squash badminton the frame of a racket 7. one of the biased wooden bowls used in the game of bowls 8. Music short for woodwind9. a. casks, barrels, etc., made of wood b. from the wood (of a beverage) from a wooden container rather than a metal or glass one

Wood

1. Mrs Henry, married name of Ellen Price. 1814--87, British novelist, noted esp for the melodramatic novel East Lynne (1861) 2. Sir Henry (Joseph). 1869--1944, English conductor, who founded the Promenade Concerts in London 3. John, known as the Elder. 1707--54, British architect and town planner, working mainly in Bath, where he designed the North and South Parades (1728) and the Circus (1754) 4. his son, John, known as the Younger. 1727--82, British architect: designed the Royal Crescent (1767--71) and the Assembly Rooms (1769--71), Bath 5. Ralph. 1715--72, British potter, working in Staffordshire, who made the first toby jug (1762)

Woods

(dreams)They may represent your unconscious or your “mental space.” If you are lost in the woods, it may be a reflection of feelings of confusion and a lack of clear direction.

Wood


Wood

(wud), Paul, U.S. cardiologist, 1907-1962. See: Wood units.

Wood

(wud), Robert, U.S. physicist, 1868-1955. See: Wood glass, Wood lamp, Wood light.

Wood,

(origin unknown). Romberg-Wood syndrome - see under Romberg, E
LegalSeeWoodsFinancialSeeWoodcutSee WD

WOOD


AcronymDefinition
WOODWorkshop on Object-Oriented Developments (various locations)
WOODWorldwide Ocean Optics Database
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