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

Illia Issaiev hated it when his family fled the fighting by crossing over into Russia.

From Barron's • Dec. 17, 2025

But that was followed by a long stretch in limbo, with albums and tours that were devoured by hardcore fans, without crossing over to the mainstream.

From BBC • Sep. 1, 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

Rain always brought her to our door, draped in a long oilskin, skirts wet from crossing over.

From "Beyond the Bright Sea" by Lauren Wolk