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

Israeli military body Cogat says approximately 1,150 people have left Gaza via the crossing over the past two months and that the same number have entered Gaza.

From BBC • Apr. 7, 2026

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

From Barron's • Dec. 17, 2025

Twenty captives were crossing over Israel’s border to jubilant homecomings, but Bipin wasn’t among them.

From The Wall Street Journal • Oct. 15, 2025

Next came an overnight bus ride to their final destination: tiny Swink, Colo., where Japanese American farmers had previously employed Alvarado’s wealthier uncles, writing a letter of recommendation this time to make crossing over easier.

From Los Angeles Times • Oct. 10, 2025

She and a group of friends had gone backcountry mountain climbing and skiing, crossing over glaciers and racing down snowy peaks hundreds of miles away from Mount St. Helens.

From "Mountain of Fire" by Rebecca E. F. Barone