acontium

noun

acon·​ti·​um

ə-ˈkän-chē-əm

plural acontia

ə-ˈkän-chē-ə

or acontiums

zoology

: one of the free threads continued from the lower ends of the septa of certain actinians, histologically similar to cnidoglandular bands, protruding through the mouth when the animal contracts, and probably defensive

Word History

Etymology

New Latin, from Greek akontion javelin, diminutive of akont-, akōn

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