X chromosome

nounGenetics.

a sex chromosome of humans and most mammals that determines femaleness when paired with another X chromosome and that occurs singly in males.

Origin of X chromosome

First recorded in 1910–15

Compare Y chromosome.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use X chromosome in a sentence

Once it was shown that women can have a single X chromosome (just as men can have two of them) that was abandoned as well.
Caster Semenya And The IOC’s Olympics Gender Bender | Jesse Ellison | July 26, 2012 | THE DAILY BEAST
The multitask gene is obviously linked to the X chromosome, because I know of no men who carry the trait.
Exactly How Are Men Superior? | Laura Bennett | January 29, 2009 | THE DAILY BEAST
This X chromosome has also the factor for the development of red-eye pigment.
The Organism as a Whole | Jacques Loeb
The chromosome situation in Protenor is a somewhat extreme case, inasmuch as one X chromosome is entirely lacking in the male.
The Organism as a Whole | Jacques Loeb
The normal red-eyed Drosophila has one kind of eggs, each possessing one X chromosome.
The Organism as a Whole | Jacques Loeb

In the latter case an egg without an X chromosome is produced.
Sex-linked Inheritance in Drosophila | Thomas Hunt Morgan
We are justified, therefore, in speaking of the factors carried by the X chromosome as sex-linked.
Sex-linked Inheritance in Drosophila | Thomas Hunt Morgan

British Dictionary definitions for X-chromosome

X-chromosome

noun

the sex chromosome that occurs in pairs in the diploid cells of the females of many animals, including humans, and as one of a pair with the Y-chromosome in those of males: Compare Y-chromosome

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for X-chromosome

X-chromosome

[ ĕks′krō′mə-sōm′ ]

The sex chromosome that in female mammals is paired with another X-chromosome and in males is paired with a Y-chromosome. Very few genes on the X-chromosome have counterparts on the Y-chromosome, and since males have only one X-chromosome, any gene present on it (even if the gene is recessive in females) is expressed in males. In females, one of the two X-chromosomes in each cell is deactivated. See more at sex chromosome. See note at sex.

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