noun ac·tin·ia \ak-ˈti-nē-ə\

Definition of actinia

  1. 1 capitalized, in some classifications :  a genus of sea anemones nearly coextensive with the order Actiniaria

  2. 2 plural actiniae \ak-ˈti-nē-ˌē\ or actinias :  any sea anemone or related animal

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Origin and Etymology of actinia

borrowed from New Latin, from Greek aktīn-, aktís “ray, beam” + New Latin -ia 1-ia — more at actino-

First Known Use: 1752

Seen and Heard

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a brief usually trivial fact

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