compression

Etymology

It is borrowed from Old French compression,^[2][3][4][5] and partly a direct borrowing of Latin compressiō (“a pressing together”),^[3][4] a noun of action formed on compressus, the past participle of comprimō (“to press together, squeeze”),^[3][2][6][7] which is built from com- (“together”) and the verb that gave press.^[8] The Middle English form was compressioun.^[6][9] In Anglo-Norman the noun is recorded from the second quarter of the 13th century.^[10]

Earliest recorded meaning

The act of pressing or squeezing something together: c. 1400, in Lanfranc's Cirurgie, a surgical treatise,^[2][9] where Middle English medical writers also used it of a constriction.^[9]

Semantic evolution

For two centuries the word belonged mainly to surgery: Middle English writers used it of pressure on the brain and of a wound bound with plaster,^[9] and in 1599 it could even name a compress itself.^[2][11] The state of being compressed is recorded from 1603, in Florio's translation of Montaigne.^[2] Johnson (1755) defined it as the forcing of a body's parts closer together "by violence".^[12] From 1759, in Samuel Johnson's Idler, it was used of thought and language packed into few words,^[2] part of a pattern, going back to the second half of the 16th century, of describing writing in terms of solidity and density.^[13] The same year it could also mean a straitened or oppressed condition.^[2][11] Engines brought technical senses: the reduction in volume of steam left in a cylinder (1859) and of the fuel and air mixture in an internal-combustion engine (1887).^[2][4] Electronics added the reduction of a signal's variability in 1938,^[2] and computing the storing of data in less space,^[14] one of many computing uses drawn from words for size since the second half of the 20th century.^[13]

Timeline

• c. 1400 – pressing together, squeezing.^[2][9]
• 1599 – a compress (obsolete, rare).^[2]
• 1603 – the state of being compressed.^[2]
• 1759 – of language, conciseness; also an oppressed condition.^[2]
• 1814 – compression of the poles, the flattening of a planet.^[2]
• 1859 – in a steam engine, the reduction in volume of steam.^[2]
• 1887 – in an internal-combustion engine;^[2][4] also compressional wave.^[3]
• 1938 – in electronics, reducing a signal's variability.^[2]

Modern meaning

Noun

1. The act of compressing something, or the state of being compressed: the compression of the spring under a heavy load.
2. In an engine, the reduction in volume of the fuel and air mixture before ignition; also the degree of this.
3. (computing) The encoding of data so that it takes up less storage space.
4. (electronics) The reduction of the range of a signal.
5. The condensing of thought or expression into few words.

Word family

• compressional
• noncompression
• overcompression
• precompression
• supercompression
• compression ratio
• compression wave

Related words

• compress
• compressor
• press
• pressure
• depression
• impression

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
6. ^ a b Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
8. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
9. ^ a b c d e Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
10. ^ Anglo-Norman Dictionary (AND2), Aberystwyth University, anglo-norman.net (2nd ed., 2005–)
11. ^ a b Kay, Christian; Roberts, Jane; Samuels, Michael; Wotherspoon, Irené, eds. (2009), Historical Thesaurus of the Oxford English Dictionary, Oxford: Oxford University Press; online edition (2024)
12. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
13. ^ a b Mapping Metaphor with the Historical Thesaurus, University of Glasgow, mappingmetaphor.arts.gla.ac.uk
14. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt