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triactinal

adjective
tri·​actinal | \(ˈ)trī¦aktənəl, ¦trīˌak¦tīnᵊl\
variants: or less commonly triactine \(ˈ)trī¦akˌtīn, -​tə̇n \

Definition of triactinal 

: having three rays a triactinal sponge spicule

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History and Etymology for triactinal

tri- + -actinal or -actine

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