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actinia

noun ac·tin·ia \ ak-ˈti-nē-ə \
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Definition of actinia

1 capitalized, in some classifications : a genus of sea anemones nearly coextensive with the order Actiniaria
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 -ia1-ia

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