crossing over

American  

noun

Genetics.

1. the interchange of corresponding chromatid segments of homologous chromosomes with their linked genes.

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crossing over British  

noun

1. biology the interchange of sections between pairing homologous chromosomes during the diplotene stage of meiosis. It results in the rearrangement of genes and produces variation in the inherited characteristics of the offspring See also linkage

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crossing over Scientific  

/ krô′sĭng-ō′vər /

1. The exchange of genetic material between homologous chromosomes that occurs during meiosis and contributes to genetic variability.

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Etymology

Origin of crossing over

First recorded in 1910–15

Example Sentences

Gold traded up 0.8% Friday, and is less than $50 away from crossing over the $5,000-per-ounce threshold for the first time.

From The Wall Street Journal • Jan. 23, 2026

“In Q3, Carvana once again drove industry-leading growth and profitability while crossing over $20 billion revenue run rate scale for the first time,” said CEO and founder Ernie Garcia.

From Barron's • Oct. 29, 2025

At the other end it took a try-saving shove from Connor to keep Bennison from crossing over on the hour mark.

From BBC • Sep. 27, 2025

The girl had been travelling with her sister, who survived the late-night crossing over the vast lake, where winds can be powerful.

From BBC • May 6, 2025

Philip Milholland’s notes were in Ishmael’s front left pants pocket, and it was just a matter of standing up, crossing over to Ed Soames, and asking to see Judge Fielding.

From "Snow Falling on Cedars: A Novel" by David Guterson