Barr body

[ bahr ]

noun

1. a condensed, inactivated X chromosome present in most female mammals in the nuclei of all cells except the germ cells: used, as in sports competitions, to verify that an individual is genetically female.

Word History and Origins

Origin of Barr body¹

First recorded in 1960–65; named after Murray L. Barr (1908–88), Canadian physician

Example Sentences

Historically, sports authorities have required female athletes to be examined naked or to undergo chromosomal testing, in which they looked for a structure called a Barr body, indicating the presence of more than one X chromosome.

From Slate