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

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

From Barron's • Dec. 17, 2025

We finally parked underneath the Little Village Arch, a colonial-style gateway crossing over the part of 26th Street where Uber dropped me off earlier.

From Los Angeles Times • Nov. 9, 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

The affair only lasted a year, but was later immortalised by the Kinks in the song Waterloo Sunset: with a line referencing Terry and Julie crossing over the river.

From BBC • Aug. 17, 2025

There was a time when my heart would play jump rope when I saw him crossing over to our house.

From "Before We Were Free" by Julia Alvarez