headroomn.

Brit.

/ˈhɛdruːm/,

/ˈhɛdrʊm/, U.S.

/ˈhɛdˌrum/,

/ˈhɛdˌrʊm/

Forms: see head n.¹ and room n.¹

Origin: Formed within English, by compounding. Etymons: head n.¹, room n.¹

Etymology: < head n.¹ + room n.¹With sense 1b compare earlier headland n. 1 and also headrig n.

†1. Scottish.

a. The crest or highest line of a hill. Obsolete.

ΚΠ

c1430 Acts Parl. Scotl. (1844) I. p. xxvii All kynd of monthis..Within Scotland hes mercheis thre, Heidrowm, watter and monthis bord.

b. The boundary portion of a piece of land; the outer or marginal strip of a holding of arable land, typically where it adjoins common grazing ground. Cf. headland n. 1. Obsolete.

ΘΚΠ

the world > space > relative position > condition of being external > edge, border, or margin > boundary > [noun]

goalc1350

bounda1387

list1389

finea1400

frontier1413

enda1425

limit1439

buttal1449

headroom1462

band1470

mete?1473

buttinga1475

bounder1505

pale?a1525

butrelle1546

scantlet1547

limesa1552

divisec1575

meta1587

line1595

marginc1595

closure1597

Rubicon1613

bournea1616

boundary1626

boundure1634

verge1660

terminary1670

meta1838

1462 Extracts Rec. in W. Chambers Charters Burgh Peebles (1872) 147 At ilke man haf his dykkis mad..sowfychand bath for front and hede rowm, and sydwawdyk.

1472 in J. D. Marwick Charters Edinb. (1871) 135 We charge al personis having tenementis or landis wythin the..burgh that thai strenth and fortify thair hede rowmys.

1653 in R. Renwick Extracts Rec. Burgh Peebles (1910) 15 To goe to the Eister Commoun daylie..and sie the yeild nolt..keept to the heid rowmes and merches apon the hest of the commonnes.

1706 in R. Renwick Extracts Rec. Royal Burgh of Lanark (1893) 273 Ane middenstead on his oun headroum.

1768 Memorial A. Macduff against Sir J. Stewart 1 The tenants and possessors..having their corn-lands or head-rooms in the lower grounds upon the river-side.

a. Space or clearance overhead; spec. (a) sufficient space to allow a person or vehicle (of a specified height) to pass under a bridge, arch, etc.; (b) room above the head of a person inside a vehicle or other confined space. Cf. headway n. 4.

ΘΚΠ

the world > space > [noun] > unobstructed space > for passing or being clear of something > overhead

head heighta1652

headway1735

headroom1762

head space1856

1762 J. Bridges Reasons for building Bridge of Three Arches 25 The Single Arch Bridge will only admit of 8 Feet Head Room.

1785 W. Marshall Planting & Ornamental Gardening 492 Leaving a side branch at least an inch in diameter..and with air and head-room enough to keep it in a flourishing state.

1832 R. Sharp Diary 15 Oct. (1997) 387 It is a foolish thing to persist in going under the Gate way, where there is not head Room sufficient.

1876 Encycl. Brit. IV. 267/2 Sufficient light, and headroom of at least 48 inches, being provided.

1912 Autocar 25 May 928/2 There is ample head room inside both for the driver and passengers, owing to the four interior arm-chairs being set well down.

1960 Farmer & Stockbreeder 15 Mar. 157 14 ft. clear headroom.

1988 Architects' Jrnl. 20 Jan. 45 The floor inside rises half a dozen steps by the time it reaches the north end, so there the ties are raised to give more headroom.

2006 Field July 125/2 Thanks to the higher roofline, rear passengers get 2in of extra headroom.

b. figurative and in extended use: scope or opportunity for freedom of action, upward movement, etc.

ΘΚΠ

society > authority > lack of subjection > freedom or liberty > freedom of action or from restraint > [noun] > scope or free opportunity

roomeOE

leisure1303

libertyc1425

free chase1467

scope1534

roomtha1540

swinge1542

swing1584

blank charter1593

freedom1623

field1639

play1641

free agencya1646

range1793

expatiationa1848

leaveway1890

open slather1919

headroom1932

1932 G. H. Thomson in Brit. Jrnl. Educ. Psychol. June 128 I mean by headroom, room at the top of the test for the cleverest children to show their powers. A test clearly has insufficient headroom if numbers of children are jammed together near the maximum possible score.

1958 Economist 20 Dec. 1103/2 Greater ‘headroom’ to make..increases in passenger fares..was the main object of the application by the Transport Commission.

1988 New Scientist 22 Oct. 49/1 A unified television system, carefully designed to leave headroom for further technical improvements.

2005 Campaign 11 Feb. 44/1 (advt.) Your profile is raised even more by your senior reporting line allowing plenty of autonomy and headroom.

3. Electronics.

a. In an audio system: the amount by which a signal can exceed the average level or normal operating level without undergoing clipping or distortion.

ΚΠ

1969 Radio & Electronic Engineer 37 201/2 Care should be taken to avoid ‘over modulation’ or severe distortion will result. In practice, it is prudent to allow a little headroom.]

1974 Pop. Mech. Apr. 137/2 Encouraged by this amplifier's headroom between average and peak signals, I've been playing it an average of 6 db louder.

1989 Broadcast 13 Oct. 77/1 (advt.) The sonic perfection of +30 dB of input and output headroom.

1994 Electronic Musician Oct. 85/3 It can cause high-frequency distortion and eat up high-frequency headroom.

2012 Engadget HD (Nexis) 6 Sept. Delivering a very transparent, accurate audio signal with a highly improved signal-to-noise ratio and increased headroom.

b. The drop in voltage between the input of a voltage regulator and the regulated output.

ΚΠ

1980 P. Horowitz & W. Hill Art of Electronics v. 176/2 This is unavoidable if the regulator chip is powered by the unregulated input, since it needs a few volts of ‘headroom’ to operate (specified by the dropout voltage).

1996 J. C. Whitaker Electronics Handbk. lxiii. 945 This is a considerable improvement from the earlier regulators requiring 2–3 V of headroom.

2011 B. Dobkin & J. Williams Analog Circuit Design iii. 22/1 (caption) High efficiency low dropout 5V switching regulator needs only 200mV headroom at 1A output.

This entry has been updated (OED Third Edition, June 2013; most recently modified version published online March 2022).

单词	headroom
释义	headroomn. Brit. /ˈhɛdruːm/, /ˈhɛdrʊm/, U.S. /ˈhɛdˌrum/, /ˈhɛdˌrʊm/ Forms: see head n.¹ and room n.¹ Origin: Formed within English, by compounding. Etymons: head n.¹, room n.¹ Etymology: < head n.¹ + room n.¹With sense 1b compare earlier headland n. 1 and also headrig n. †1. Scottish. a. The crest or highest line of a hill. Obsolete. ΚΠ c1430 Acts Parl. Scotl. (1844) I. p. xxvii All kynd of monthis..Within Scotland hes mercheis thre, Heidrowm, watter and monthis bord. b. The boundary portion of a piece of land; the outer or marginal strip of a holding of arable land, typically where it adjoins common grazing ground. Cf. headland n. 1. Obsolete. ΘΚΠ the world > space > relative position > condition of being external > edge, border, or margin > boundary > [noun] goalc1350 bounda1387 list1389 finea1400 frontier1413 enda1425 limit1439 buttal1449 headroom1462 band1470 mete?1473 buttinga1475 bounder1505 pale?a1525 butrelle1546 scantlet1547 limesa1552 divisec1575 meta1587 line1595 marginc1595 closure1597 Rubicon1613 bournea1616 boundary1626 boundure1634 verge1660 terminary1670 meta1838 1462 Extracts Rec. in W. Chambers Charters Burgh Peebles (1872) 147 At ilke man haf his dykkis mad..sowfychand bath for front and hede rowm, and sydwawdyk. 1472 in J. D. Marwick Charters Edinb. (1871) 135 We charge al personis having tenementis or landis wythin the..burgh that thai strenth and fortify thair hede rowmys. 1653 in R. Renwick Extracts Rec. Burgh Peebles (1910) 15 To goe to the Eister Commoun daylie..and sie the yeild nolt..keept to the heid rowmes and merches apon the hest of the commonnes. 1706 in R. Renwick Extracts Rec. Royal Burgh of Lanark (1893) 273 Ane middenstead on his oun headroum. 1768 Memorial A. Macduff against Sir J. Stewart 1 The tenants and possessors..having their corn-lands or head-rooms in the lower grounds upon the river-side. 2. a. Space or clearance overhead; spec. (a) sufficient space to allow a person or vehicle (of a specified height) to pass under a bridge, arch, etc.; (b) room above the head of a person inside a vehicle or other confined space. Cf. headway n. 4. ΘΚΠ the world > space > [noun] > unobstructed space > for passing or being clear of something > overhead head heighta1652 headway1735 headroom1762 head space1856 1762 J. Bridges Reasons for building Bridge of Three Arches 25 The Single Arch Bridge will only admit of 8 Feet Head Room. 1785 W. Marshall Planting & Ornamental Gardening 492 Leaving a side branch at least an inch in diameter..and with air and head-room enough to keep it in a flourishing state. 1832 R. Sharp Diary 15 Oct. (1997) 387 It is a foolish thing to persist in going under the Gate way, where there is not head Room sufficient. 1876 Encycl. Brit. IV. 267/2 Sufficient light, and headroom of at least 48 inches, being provided. 1912 Autocar 25 May 928/2 There is ample head room inside both for the driver and passengers, owing to the four interior arm-chairs being set well down. 1960 Farmer & Stockbreeder 15 Mar. 157 14 ft. clear headroom. 1988 Architects' Jrnl. 20 Jan. 45 The floor inside rises half a dozen steps by the time it reaches the north end, so there the ties are raised to give more headroom. 2006 Field July 125/2 Thanks to the higher roofline, rear passengers get 2in of extra headroom. b. figurative and in extended use: scope or opportunity for freedom of action, upward movement, etc. ΘΚΠ society > authority > lack of subjection > freedom or liberty > freedom of action or from restraint > [noun] > scope or free opportunity roomeOE leisure1303 libertyc1425 free chase1467 scope1534 roomtha1540 swinge1542 swing1584 blank charter1593 freedom1623 field1639 play1641 free agencya1646 range1793 expatiationa1848 leaveway1890 open slather1919 headroom1932 1932 G. H. Thomson in Brit. Jrnl. Educ. Psychol. June 128 I mean by headroom, room at the top of the test for the cleverest children to show their powers. A test clearly has insufficient headroom if numbers of children are jammed together near the maximum possible score. 1958 Economist 20 Dec. 1103/2 Greater ‘headroom’ to make..increases in passenger fares..was the main object of the application by the Transport Commission. 1988 New Scientist 22 Oct. 49/1 A unified television system, carefully designed to leave headroom for further technical improvements. 2005 Campaign 11 Feb. 44/1 (advt.) Your profile is raised even more by your senior reporting line allowing plenty of autonomy and headroom. 3. Electronics. a. In an audio system: the amount by which a signal can exceed the average level or normal operating level without undergoing clipping or distortion. ΚΠ 1969 Radio & Electronic Engineer 37 201/2 Care should be taken to avoid ‘over modulation’ or severe distortion will result. In practice, it is prudent to allow a little headroom.] 1974 Pop. Mech. Apr. 137/2 Encouraged by this amplifier's headroom between average and peak signals, I've been playing it an average of 6 db louder. 1989 Broadcast 13 Oct. 77/1 (advt.) The sonic perfection of +30 dB of input and output headroom. 1994 Electronic Musician Oct. 85/3 It can cause high-frequency distortion and eat up high-frequency headroom. 2012 Engadget HD (Nexis) 6 Sept. Delivering a very transparent, accurate audio signal with a highly improved signal-to-noise ratio and increased headroom. b. The drop in voltage between the input of a voltage regulator and the regulated output. ΚΠ 1980 P. Horowitz & W. Hill Art of Electronics v. 176/2 This is unavoidable if the regulator chip is powered by the unregulated input, since it needs a few volts of ‘headroom’ to operate (specified by the dropout voltage). 1996 J. C. Whitaker Electronics Handbk. lxiii. 945 This is a considerable improvement from the earlier regulators requiring 2–3 V of headroom. 2011 B. Dobkin & J. Williams Analog Circuit Design iii. 22/1 (caption) High efficiency low dropout 5V switching regulator needs only 200mV headroom at 1A output. This entry has been updated (OED Third Edition, June 2013; most recently modified version published online March 2022). < n.c1430
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