diactine

noun

di·​ac·​tine

(ˈ)dīˈakˌtīn,

-tə̇n

variants or diact

ˈdīˌakt

or less commonly diactin

(ˈ)dīˈaktə̇n

plural -s

: a sponge spicule having two pointed arms

Word History

Etymology

di- + Greek aktin-, aktis ray

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