A tuft of hair on the human forehead, sometimes called a feather; it cannot be made to lie in the same direction as the rest of the hair by brushing, or even by pomatum. When cows lick their hides they make the hair stand on end.
“This term must have been adopted from a comparison with that part of a ... cow's hide where the hairs, having different directions, meet and form a projecting ridge, supposed to be occasioned by the animals licking themselves.” —Brochett: Glossary of North-Country Words.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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