Definition of osmeterium in English:

osmeterium

(also osmaterium)

noun

Entomology
  • An organ capable of emitting a penetrating or noxious odour; specifically an eversible gland on the first thoracic segment of certain papilionid caterpillars.

Origin

Early 19th century; earliest use found in William Kirby (1759–1850), entomologist and naturalist. From ancient Greek ὀσμᾶσθαι to smell (from ὀσμή smell: see osmo-) + -τήριον, suffix forming nouns.

Pronunciation

osmeterium

/ˌɒsmɪˈtɪərɪəm/