aculeus

noun

acu·​le·​us

ə-ˈkyü-lē-əs

plural aculei

ə-ˈkyü-lē-ˌī

zoology

: a sharp-pointed process

specifically : an insect's ovipositor especially when modified into a sting

Word History

Etymology

borrowed from New Latin, going back to Latin, "stinger, spine (of a fish), sharp point, barb," from acū-, stem of acus "needle" + -leus, noun suffix (perhaps originally diminutive)

First Known Use

1702, in the meaning defined above

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