crossing-over

noun

cross·ing-over ˌkrȯ-siŋ-ˈō-vər

: an interchange of genes or segments between homologous chromosomes

Word History

First Known Use

1912, in the meaning defined above

Time Traveler

The first known use of crossing-over was in 1912

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Cite this Entry

Style

“Crossing-over.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/crossing-over. Accessed 4 Feb. 2026.

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Kids Definition

crossing-over

noun

cross·ing-over

ˌkrȯ-siŋ-ˈō-vər

: an exchange of genes or chromosome segments between corresponding parts of similar but usually not identical chromosomes during meiosis

Medical Definition

crossing-over

noun

cross·ing-over ˌkrȯ-siŋ-ˈō-vər

: an interchange of genes or segments between homologous chromosomes

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