plural noun

Definition of Allotheria

: 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

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First Known Use of Allotheria

1880, in the meaning defined above

History and Etymology for Allotheria

New Latin, from all- + -theria

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The first known use of Allotheria was in 1880

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very full or close together

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