capitalized in some classifications : a genus of sea anemones nearly coextensive with the order Actiniaria
plural actiniae
or actinias : any sea anemone or related animal

Word History


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

First Known Use

1752, in the meaning defined at sense 1

Time Traveler
The first known use of actinia was in 1752

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Dictionary Entries Near actinia

Cite this Entry

“Actinia.” Dictionary, Merriam-Webster, Accessed 21 Jun. 2024.

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