the·​ri·​an ˈthir-ē-ən How to pronounce therian (audio)
: any of a subclass (Theria) of mammals comprising the marsupials and the placental mammals
therian adjective

Word History


New Latin Theria, from Greek thēria, plural of therion wild animal — more at treacle

First Known Use

1962, in the meaning defined above

Time Traveler
The first known use of therian was in 1962

Dictionary Entries Near therian

Cite this Entry

“Therian.” Dictionary, Merriam-Webster, Accessed 14 Jun. 2024.

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