innocuous

Etymology

It is borrowed from Latin innocuus (“harmless”), with the English suffix -ous.^[2][3][4][5] The Latin adjective is formed from in- (“not”) and nocuus (“hurtful”),^[3][6][2][7] from the root of noceō (“to harm, hurt”),^[3][6][8] from Proto-Indo-European *nek- (“death”).^[7][6] It is related to innocent and noxious.^[5][2][8]

Earliest recorded meaning

Harmless, causing no injury: 1598 in Barnhart and Merriam-Webster,^[2][8] the 1590s in Etymonline;^[7] the OED's first record is from 1631, in Barckley's Discourse of the Felicitie of Man.^[3]

Semantic evolution

The word first described things that do no harm, such as a substance or a remedy;^[3][9] Johnson (1755) defined it as "harmless in effects", quoting Grew on poisons made innocuous.^[9] In zoology it was applied to the non-venomous snakes.^[3] It later came to mean also inoffensive, unlikely to provoke anyone, and so bland or insignificant.^[8][4]

Timeline

• 1598 – harmless, causing no injury.^[2][8] The OED's first record is from 1631.^[3]

Meanings

Adjective

1. Having no harmful effect; harmless: The mushroom looks dangerous but is innocuous.^[10][8][3]
2. Not likely to offend or provoke; inoffensive: an innocuous remark.^[8][4]
3. Not likely to arouse strong feelings; insipid or dull.^[8]

Word family

• innocuously
• innocuousness
• uninnocuous

Related words

• innocent
• noxious
• nocuous
• innoxious

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
3. ^ a b c d e f g h Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
4. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
7. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
8. ^ a b c d e f g h Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
9. ^ a b Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
10. ^ Collins English Dictionary (2023), Glasgow: HarperCollins