hispid cotton rat

noun

: a cotton rat (Sigmodon hispidus) of the southern and central U.S. that has a grizzled coat of dark hairs interspersed with buff or grayish hairs, nests on the ground or in burrows, eats primarily green vegetation, and is sometimes used in medicine as an animal model in the study of infectious disease (such as polio and influenza)

Word History

First Known Use

1905, in the meaning defined above

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