Y chromosome

American  

noun

Genetics.

1. a sex chromosome of humans and most mammals that is present only in males and is paired with an X chromosome.

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Y-chromosome British  

noun

1. the sex chromosome that occurs as one of a pair with the X-chromosome in the diploid cells of the males of many animals, including humans Compare X-chromosome

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Y-chromosome Scientific  

1. The sex chromosome that is paired with an X-chromosome in males. Most of the genes on the X-chromosome determine physical attributes associated with males, such as the development of testes.

2. See more at sex chromosome See Note at sex

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Etymology

Origin of Y chromosome

First recorded in 1920–25

Example Sentences

"While the direct evidence of physical advantage in transgender people is pretty strong, the evidence of advantage for those with DSD, even though they have a Y chromosome, is highly disputed."

From BBC • Mar. 31, 2026

Advances in genetic detection have revealed that Y chromosome loss is widespread in older men.

From Science Daily • Mar. 20, 2026

Instead, it creates a mix of cells with and without the Y chromosome, a condition known as mosaicism.

From Science Daily • Mar. 20, 2026

There are also signs that Y chromosome loss can directly influence cancer behavior.

From Science Daily • Mar. 20, 2026

The females that gave these results were found by Bridges to have two X's and a Y chromosome.

From A Critique of the Theory of Evolution by Morgan, Thomas Hunt