X chromosome

noun

: a sex chromosome that usually occurs paired in each female cell and single in each male cell in species in which the male typically has two unlike sex chromosomes compare y chromosome

Examples of X chromosome in a Sentence

Recent Examples on the Web

His theory suggested that orange coat color was controlled by a variant on the X chromosome, explaining why ginger cats are mostly male and why tortoiseshell cats, with their mix of orange and non-orange fur, are almost always female. —Daniel R. Depetris, Newsweek, 6 Dec. 2024

Biological females typically have two X chromosomes (XX), and biological males typically have one X and one Y chromosome (XY). —Loreben Tuquero, Austin American-Statesman, 7 Aug. 2024

Newsletter Sign up for our email newsletter for the latest science news A simple difference in the genetic code – two X chromosomes versus one X chromosome and one Y chromosome – can lead to major differences in heart disease. —Amy Huebschmann, Discover Magazine, 24 Oct. 2024

Women have two X chromosomes, while men have just one. —Sarah Kuta, Smithsonian Magazine, 23 Sep. 2024

Word History

First Known Use

1911, in the meaning defined above

Kids Definition

X chromosome

noun

: a sex chromosome that is associated with femaleness and usually occurs paired in each female cell and single in each male cell in organisms (as human beings) in which the male normally has two unlike sex chromosomes compare y chromosome

Medical Definition

X chromosome

noun

: a sex chromosome that usually occurs paired in each female cell and single in each male cell in species in which the male typically has two unlike sex chromosomes compare y chromosome