: a densely staining inactivated condensed X chromosome that is present in each somatic cell of most female mammals and is used as a test of genetic femaleness (as in a fetus)
called also sex chromatin
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The inactivated chromosome can be seen under a microscope as a tiny dark Barr body compacted inside cells.
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Grrlscientist, Forbes.com, 2 June 2025
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Grrlscientist, Forbes.com, 2 June 2025
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“Barr body.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Barr%20body. Accessed 30 Oct. 2025.
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Barr body
noun
: a densely staining inactivated condensed X chromosome that is present in each somatic cell of most female mammals and is used as a test of genetic femaleness (as in a fetus or an athlete)
called also sex chromatin
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