chiasma

noun
chi·​as·​ma | \ kī-ˈaz-mə How to pronounce chiasma (audio) , kē- \
plural chiasmata\ kī-​ˈaz-​mə-​tə How to pronounce chiasma (audio) , kē-​ \

Definition of chiasma

1 : an anatomical intersection or decussation — compare optic chiasma
2 : a cross-shaped configuration of paired chromatids visible in the diplotene stage of meiotic prophase and considered the cytological equivalent of genetic crossing-over

Other Words from chiasma

chiasmatic \ ˌkī-​əz-​ˈma-​tik How to pronounce chiasma (audio) , ˌkē-​ \ adjective

First Known Use of chiasma

1839, in the meaning defined at sense 1

History and Etymology for chiasma

New Latin, X-shaped configuration, from Greek, crosspiece, from chiazein to mark with a chi, from chi (x)

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The first known use of chiasma was in 1839

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Cite this Entry

“Chiasma.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chiasma. Accessed 27 Feb. 2021.

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More Definitions for chiasma

chiasma

noun
chi·​as·​ma | \ kī-ˈaz-mə, kē- How to pronounce chiasma (audio) \
plural chiasmata\ -​mət-​ə How to pronounce chiasma (audio) \

Medical Definition of chiasma

1 : an anatomical intersection or decussation — see optic chiasma
2 : a cross-shaped configuration of paired chromatids visible in the diplotene of meiotic prophase and considered the cytological equivalent of genetic crossing-over

Other Words from chiasma

chiasmatic \ ˌkī-​əz-​ˈmat-​ik, ˌkē-​ How to pronounce chiasma (audio) \ adjective

More from Merriam-Webster on chiasma

Britannica.com: Encyclopedia article about chiasma

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