Hydractinia

noun Hy·drac·tin·ia \ ˌhīˌdrakˈtinēə \

Definition of Hydractinia

: a genus of marine hydroids that have separate and distinctive polyps for nutritive, reproductive, and defensive functions borne on a dense encrusting coenosarc and that are commonly associated with shells containing hermit crabs

hydractinian

adjective or noun

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Origin and Etymology of hydractinia

New Latin, from hydr- + Actinia


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