syn·​ap·​sis | \ sə-ˈnap-səs How to pronounce synapsis (audio) \
plural synapses\ sə-​ˈnap-​ˌsēz How to pronounce synapses (audio) \

Definition of synapsis

: the association of homologous chromosomes that is characteristic of the first meiotic prophase

Examples of synapsis in a Sentence

Recent Examples on the Web

The text spasms with memory like synapses firing in the dark. Barbara Vandenburgh, USA TODAY, "Ocean Vuong's 'On Earth We're Briefly Gorgeous' a transcendent queer immigrant story," 5 June 2019 Intriguingly, nearly 80 percent of the proteins — 69 of them — are involved in the synapses, the places where neurons connect to one another. Quanta Magazine, "You Are Getting Sleepy — Tagged Proteins May Point to Why," 21 Aug. 2018 By his second birthday, synapses are forming for language and many other higher cognitive functions. Meghan Cox Gurdon, WSJ, "The Secret Power of the Children’s Picture Book," 18 Jan. 2019 Most of the RNAs that were under-edited in autistic brains relative to control brains come from genes that are involved in the transmission of glutamate, a vital neurotransmitter, across synapses. Diana Gitig, Ars Technica, "Autism involves a large-scale reduction in RNA editing," 21 Dec. 2018 Recent images of slices of a mouse brain require a supercomputer to assemble them into a 3D model of individual neurons and synapses. Ernie Mastroianni, Discover Magazine, "Meet the Man Who Takes Pictures of Microbes," 18 Oct. 2018 Each neuron should have an average of 7,000 connections, mostly through synapses, empty space that must be crossed by chemicals. Jacqueline Detwiler, Popular Mechanics, "The Heroes of Science Who Are Unlocking the Brain," 3 Oct. 2018 Some synapses get pruned, all making the brain more efficient. Karen Campbell,, "Her quest to understand the teenage brain," 12 July 2018 Counsell, usually not much for milestones, offered a quick synapsis of his team's standing. Todd Rosiak, Milwaukee Journal Sentinel, "Brewers' depth once again pays dividends thanks to Keon Broxton," 29 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'synapsis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of synapsis

1895, in the meaning defined above

History and Etymology for synapsis

New Latin

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Statistics for synapsis

Last Updated

21 Jun 2019

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Time Traveler for synapsis

The first known use of synapsis was in 1895

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More Definitions for synapsis


syn·​ap·​sis | \ sə-ˈnap-səs How to pronounce synapsis (audio) \
plural synapses\ -​ˌsēz How to pronounce synapses (audio) \

Medical Definition of synapsis

: the association of homologous chromosomes with chiasma formation that is characteristic of the first meiotic prophase and is held to be the mechanism for genetic crossing-over

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showing courage and determination

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