Allotheria

plural noun

Al·​lo·​the·​ria

: a subclass of Mammalia comprising small primitive forms extinct since the early Cenozoic, being usually considered coextensive with the Multituberculata but sometimes extended to include the Protodonta and Triconodonta

Word History

Etymology

New Latin, from all- + -theria

First Known Use

1880, in the meaning defined above

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