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

They overwhelmed their visitors in the second half, with Amy Cokayne, Moloney-MacDonald and Jess Breach crossing over before Packer bagged her second of the afternoon.

From BBC • Apr. 25, 2026

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

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

“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

A streetlight outside the nearest window to the left cast stripes through the blinds onto Javier’s skin while he was in the kitchen, crossing over his shoulders and down his arms.

From "Anger Is a Gift" by Mark Oshiro