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• Y chromosome
  Y chromosome

  noun

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

  noun

  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

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

It remains challenging to determine whether losing the Y chromosome directly causes disease or simply occurs alongside it.

From Science Daily • Mar. 20, 2026

Given this history, losing the Y chromosome later in life was once considered insignificant.

From Science Daily • Mar. 20, 2026

Despite earlier assumptions, growing evidence connects Y chromosome loss to major health conditions.

From Science Daily • Mar. 20, 2026

The X chromosome in the male is represented by an open bar, the Y chromosome is bent.

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