triactinal

adjective

tri·​actinal

(ˈ)trī¦aktənəl,

¦trīˌak¦tīnᵊl

variants or less commonly triactine

(ˈ)trī¦akˌtīn,

-tə̇n

: having three rays

a triactinal sponge spicule

Word History

Etymology

tri- + -actinal or -actine

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