ppl. a. [f. COMPRESS v. + -ED.]
1. Pressed together closely, so as to occupy small space; pressed into a smaller volume and denser composition than the ordinary; condensed.
Compressed air has, from its elasticity, been applied as a motive force or substitute for steam, and is also used in Med.; hence such phrasal comb. as compressed air engine, compressed air bath (sometimes hyphened).
c. 1374. Chaucer, Boeth., II. vii. 57. Sest þou nat þan how streit and how compressed [ante so streyt yþrongen] is þilke glorie þat ȝe trauailen aboute to shew and to multiplie.
1669. Boyle, Contn. New Exp., II. (1682), 128. The compressed air suddenly finding out a way of eruption.
1731–59. Miller, Gard. Dict., s.v. Wind, Compress’d Air is denser than Air less compress’d.
1857. Engineer, IV. 144/1. Making compressed yeast.
1874. Knight, Dict. Mech., I. 30/2. Ware’s Compressed Air-bath is for subjecting a patient to an enveloping atmosphere of air under pressure. Ibid., 602/2. The compressed-air engine at Ardsley Colliery … travels on wheels and is pushed to its work by hand. Ibid., 604/1. A machine for making compressed bullets.
1879. Daily News, 16 Dec., 5/8. The compressed gas being driven into a strong boiler.
1885. Pall Mall G., 13 May, 2/2.
b. Compressed score: a musical score in which more than one voice-part is written on a single staff: esp. four-part harmony written on two staves.
1877. (title) The Congregational Psalmist: a companion to all the new Hymn-books … Compressed Score edition.
c. fig. Concentrated; condensed.
1822. T. Taylor, Apuleius, v. 105. Furnished with more compressed thoughts.
1851–5. Brimley, Ess., Tennyson, 96. ‘Love thou thy Land’ is only to be compared with an essay of Lord Bacon’s for its compressed energy.
1871. Farrar, Witn. Hist., 130. The compressed and haughty page of Tacitus.
2. Having a flattened form, like the result of pressure; having the two opposite sides nearly plane or flat; spec. in Zool. and Bot. flattened laterally, or along its length.
1668. Wilkins, Real Char., 112. A small compressed seed.
1753. Chambers, Cycl. Supp., s.v. Leaf. Compressed leaf, one with the mark of an impression on both sides.
1797. Bewick, Brit. Birds (1847), I. 293. The bill is two inches long, vertically compressed on the sides.
1816. Playfair, Nat. Phil., II. 179. Mars … is compressed at the poles, so that his equatorial diameter is to his polar axis as 16 to 15 nearly.
1849. Sk. Nat. Hist., Mammalia, IV. 201. The hand … is furnished with five powerful but compressed nails.
1882. Vines, Sachs’ Bot., 620. The stem then becomes cylindrical, or, if it is compressed … still with a uniform breadth.
b. Printing. Compressed type: = condensed type, or a variety thereof.
1875. Ure, Dict. Manuf., III. 641. Types … have undergone every change in form that fancy or taste could suggest … clarendon, a modification of antique … compressed, or tall thin letters.
3. Of separate things: Pressed together.
1847. Lytton, Lucretia, I. Prol. His compressed lips told that he felt the anguish of the laugh that circled round him.
