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density|ˈdɛnsɪtɪ|
[a. F. densité (Paré, 16th c., in 13th c. dempsité), ad. L. densitās, -tātem thickness, f. densus dense.]
1. The quality or condition of being dense; thickness; closeness of texture or consistence.
1603Holland Plutarch's Mor. 1187 The densitie and thicknesse of the aire. 1626Bacon Sylva § 592 As for the Leaves, their density appeareth in that, either they are smooth and shining..or in that they are hard and spiry. 1755Mem. Capt. P. Drake I. xvii. 185 A Fogg of the greatest Density I ever remember to have seen. 1796Morse Amer. Geog. II. 311 It was..necessary to supply the defect of density by more frequent inspirations. 1864Bowen Logic xi. (1870) 361 The additional qualities of weight, attraction, impenetrability, elasticity, density.
2. a. Physics. The degree of consistence of a body or substance, measured by the ratio of the mass to the volume, or by the quantity of matter in a unit of bulk.
1665Phil. Trans. I. 31 There is in the Air..such a variety..both as to their density and rarity. 1696Whiston Th. Earth ii. (1722) 221 More than four times the density of Water. 1726tr. Gregory's Astron. I. 147 The quantity of Matter is as the Magnitude and Density conjunctly. 1831Brewster Optics iii. 25 The bodies contained in these tables have all different densities. 1881Williamson in Nature No. 618. 415 To determine the vapour densities and rates of diffusion of those which could be obtained in the gaseous state.
b. Electr. The quantity of electricity per unit of volume or area.
1873Clerk Maxwell Electr. & Magn. (1881) §64 The electric density at a given point on a surface is the limiting ratio of the quantity of electricity within a sphere whose centre is the given point to the area of the surface contained within the sphere, when its radius is diminished without limit. 1885Watson & Burbury Math. Th. Electr. & Magn. I. 139 A uniform ring of electricity of density - 1.
3. a. Crowded state; degree of aggregation.
1851Nichol Archit. Heav. 154 Not..to sound depths by ordinary rules founded on the numbers of the stars, but rather to unfold densities. 1888Bryce Amer. Commw. II. xxxvi. 5 Not only these differences in size, but the differences in density of population.
b. concr. A dense mass or aggregation. rare.
1858Hawthorne Fr. & It. Jrnls. I. 144 Stems, supporting a cloud-like density of boughs.
4. Photogr. Opaqueness of the developed actinized film in a negative.
1879Cassell's Techn. Educ. III. 143 (Photogr.) A rapid acquisition of density will be the result. 1967E. Chambers Photolitho-Offset 271 Density, the quantitative measure of the blackening of a photographic emulsion.
5. fig. Stupidity, crassitude.
1894A. Birrell in Westminst. Budget 27 July 48/2 The density which is sometimes..attributed to your party.
Add:[2.] c. Computing. = packing density s.v. packing vbl. n.1 3 c.
1956M. V. Wilkes Automatic Digital Computers 178 A recording density of 100 digits per inch..may be used with complete success on a drum about 10 in. in diameter. 1976Electronic Electro-Optic Infrared Countermeasures June 33/2 (caption) Large-scale integration of mnos transistors permits a memory density of 2048 bits on a 154-mil by 170-mil chip. 1980C. S. French Computer Sci. iv. 15 The density of recording can vary between 200–6,250 characters to the inch. 1986ZX Computing Monthly Oct. 78/3 Although eight inch drives are limited to single density, all other drives may be single, double or quad density. |