ac·​tin·​ia | \ ak-ˈti-nē-ə \

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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First Known Use of actinia

1752, in the meaning defined at sense 1

History and Etymology for actinia

borrowed from New Latin, from Greek aktīn-, aktís “ray, beam” + New Latin -ia -ia entry 1

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Cite this Entry

“Actinia.” Dictionary, Merriam-Webster, Accessed 21 Oct. 2020.

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