Etymograph

English

innocuous

Innocuous comes from Latin innocuus ‘harmless’, from nocuus ‘harmful’, and ultimately from Proto-Indo-European *neḱ- ‘to perish, disappear’.

  1. Proto-Indo-Europeanc. 4500–2500 BCE*neḱ-1‘to perish, disappear’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*noḱéyeti1‘to make disappear, to cause death’reconstructed
  3. Proto-Italicc. 1500–700 BCE*nokeō1‘to harm, hurt, injure’reconstructed
  4. Latinc. 75 BCE–200 CEnoceō1‘to harm, damage’
  5. Latinc. 75 BCE–200 CEnocuus2‘harmful’
  6. Latinc. 75 BCE–200 CEinnocuus3‘harmless’
  7. Englishearliest quotation 1838innocuous3

attested reconstructed ? uncertain or disputed deepest recorded ancestor

  1. 1 Wiktionary, Latin nocuus
  2. 2 Wiktionary, Latin innocuus
  3. 3 Wiktionary, English innocuous
  4. Earliest quotation in Wiktionary’s entry: 1838, Richard Chenevix Trench, Sonnet I. To England. In the Tyrol.: “With its green cupola or tapering spire, / Which…”.

Lineage

  1. Proto-Indo-Europeanc. 4500–2500 BCE*neḱ-Wiktionary, Latin nocuus‘to perish, disappear’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*noḱéyetiWiktionary, Latin nocuus‘to make disappear, to cause death’reconstructed
  3. Proto-Italicc. 1500–700 BCE*nokeōWiktionary, Latin nocuus‘to harm, hurt, injure’reconstructed
  4. Latinc. 75 BCE–200 CEnoceōWiktionary, Latin nocuus‘to harm, damage’
  5. Latinc. 75 BCE–200 CEnocuusWiktionary, Latin innocuus‘harmful’
  6. Latinc. 75 BCE–200 CEinnocuusWiktionary, English innocuous‘harmless’
  7. Englishearliest quotation 1838innocuousWiktionary, English innocuous. Earliest quotation in Wiktionary’s entry: 1838, Richard Chenevix Trench, Sonnet I. To England. In the Tyrol.: “With its green cupola or tapering spire, / Which…”

Linked words

through Proto-Indo-European *neḱ- ‘to perish, disappear’

nectar, obnoxious, necropolis, internecine, 19 more

through Latin noceō ‘to harm, damage’

nuisance, innocence, noxious, 14 more

Today it means

adj Harmless; producing no ill effect.

Sources

Sources: Wiktionary, “innocuous”; the older steps come from the Wiktionary entries for Latin nocuus, Latin innocuus. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.

Etymograph / Proto-Indo-European *neḱ- / innocuous

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