Definition of Allen's rule in English:

Allen's rule

noun

Zoology
  • An empirical rule according to which the appendages of a warm-blooded animal are smaller in populations occupying the cooler parts of its geographical range.

Origin

1930s; earliest use found in Warder Clyde Allee (1885–1955). From the genitive of the name of Joel A. Allen, United States zoologist, who first formulated the rule in 1877 ( Radical Rev. 1 116) + rule.

Pronunciation

Allen's rule

/ˈalənz ˌruːl/