Allen's rule


: a statement in zoology: protruding body parts (as ears, tail, legs, bill) of warm-blooded animals are relatively shorter in cooler than in warmer parts of the range

Word History


after Joel A. Allen

First Known Use

1937, in the meaning defined above

Time Traveler
The first known use of Allen's rule was in 1937

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Dictionary Entries Near Allen's rule

Cite this Entry

“Allen's rule.” Dictionary, Merriam-Webster, Accessed 19 May. 2024.

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