contagious

Etymology

It is inherited from Middle English contagious,^[2] borrowed from Old French contagieus (modern contagieux),^[3][4][5][6] and directly borrowed from Late Latin contāgiōsus,^[4][7][8][9] from contāgiō (“a touching, contact”),^[4][5][7] with the suffix -ōsus, English -ous.^[7][3] The Latin noun comes from contingō (“to touch”), formed from com- (“with, together”) and tangō (“to touch”), from Proto-Indo-European *tag- (“to touch, handle”).^[4] The Latin word was often used in a bad sense, of contact with something physically or morally unclean.^[4]

Earliest recorded meaning

Characterized by contagion, passing on disease or corruption by contact: about 1374, in Chaucer's translation of Boethius,^[3] where Benson's concordance glosses it "corrupting, evil".^[10] The Middle English Dictionary also records it, before 1398 in Trevisa, of contaminated air and of a dragon's "contagious blastes" that corrupt the air.^[2]

Semantic evolution

Etymonline gives three late 14th-century senses: contaminating or contaminated (of air or water), communicable (of disease), and morally corrupting.^[4] It was used of diseases themselves from about 1400,^[3][2] and of persons or things carrying the germs of a disease from 1584.^[3] A wider set of senses, breeding disease, harmful or noxious in general, and morally or socially pernicious, was current from the 15th century but had died out by the late 18th.^[3][8] The figurative sense, readily passed from one person to another, as of laughter or a mood, is recorded from 1660, in R. Boyle.^[3][4] Johnson (1755) defined it as "infectious; caught by approach; poisonous; pestilential".^[11] In Irish English of the 19th century the word was used for "near, contiguous",^[12] a gloss that Skeat also gives for one passage of Chaucer.^[13]

Timeline

• c. 1374 – of the nature of contagion; passing on disease or corruption by contact.^[3]
• before 1398 – of air, contaminated, harmful.^[2]
• c. 1400 – of a disease, communicable by contact.^[3][2]
• 1495 – breeding disease, pestilential (obsolete by 1792).^[3]
• 1584 – carrying the germs of an infectious disease.^[3]
• 1660 – figurative, apt to spread from one person to another.^[3][4]
• 1866 – the Contagious Diseases Acts, against venereal disease.^[3]

Meanings

Adjective

1. Of a disease, passed on by direct or indirect contact with an infected person or with something they have handled; compare infectious.^[14][6][15]
2. Of a person or animal, carrying and able to spread such a disease: The doctor said the child was no longer contagious.^[14][6]
3. Of a feeling, attitude or mood, likely to spread to others: His laughter was contagious.^[15][14][3]
4. (obsolete) Breeding disease; pestilential, harmful or noxious.^[3][8]

Word family

• contagiously
• contagiousness
• anticontagious
• uncontagious
• contagion
• contagious magic
• contagious abortion

Related words

• contact
• contiguous
• contingent
• tangible
• tact
• infectious

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ 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)
3. ^ a b c d e f g h i j k l m n o Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
4. ^ a b c d e f g h Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ a b c Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
8. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
9. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
10. ^ Benson, Larry D., Glossarial Concordance to Middle English (Chaucer, Gower), Johns Hopkins University, github.com/jhu-digital-manuscripts/gcme
11. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
12. ^ Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)
13. ^ Skeat, W. W., ed. (1894), The Complete Works of Geoffrey Chaucer, vol. VI: Glossarial Index, Oxford: Clarendon Press
14. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
15. ^ a b Soanes, Catherine; Stevenson, Angus, eds. (2004), Concise Oxford English Dictionary, 11th ed., Oxford: Oxford University Press