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

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Other Words from Hydractinia

hydractinian \ ¦⸗ˌ⸗¦tinēən \ adjective or noun

History and Etymology for Hydractinia

New Latin, from hydr- + Actinia

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to corrupt or become corrupted

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