actine

1 of 2

noun

ac·​tine

ˈak-ˌtīn,

-tən

plural -s

: a star-shaped spicule (as of a sponge)

-actine

2 of 2

adjective combining form

¦ak-(ˌ)tīn,

-tən

: having (such or so many) rays

discoactine

pentactine

—especially in terms applied to sponge spicules

Word History

Etymology

Noun

Greek aktin-, aktis ray

Adjective combining form

Greek aktin-, aktis

First Known Use

Noun

1887, in the meaning defined above

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