brood patch

noun

: a featherless, fluid-filled area on the abdomen or breast of birds that is filled with surface blood vessels which are used to apply heat to the eggs during incubation

It was an adult female, identifiable by its brood patch: a featherless area that females develop seasonally so that first their eggs and then their young can be warmed against the mother's skin.

—Roberta Hershenson, New York Times, 2 Aug. 1992

Pressed against the parent's warm brood patch, the single egg easily weathers brief storms.

—Natural History, November 1990

Word History

First Known Use

1928, in the meaning defined above

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