episome

noun

epi·​some ˈe-pə-ˌsōm How to pronounce episome (audio) -ˌzōm How to pronounce episome (audio)
: a genetic determinant (such as the DNA of some bacteriophages) that can replicate autonomously in bacterial cytoplasm or as an integral part of the chromosomes
episomal
ˌe-pə-ˈsō-məl How to pronounce episome (audio) -ˈzō- How to pronounce episome (audio)
adjective
episomally
ˌe-pə-ˈsō-mə-lē How to pronounce episome (audio)
-ˈzō-
adverb

Examples of episome in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The latent virus may integrate into the human genome – as does HIV, for example – or exist in the nucleus as a self-replicating piece of DNA called an episome. — William Petri, The Conversation, 31 July 2020

Word History

Etymology

borrowed from French épisome, from épi- epi- + -some -some entry 3

Note: The term was introduced by the French biologists François Jacob (1920-2013) and Élie Wollman (1917-2008) in "Les épisomes, éléments génétiques ajoutés," Comptes rendus hebdomadaires des séances de l'Académie des Sciences, tome 247, première partie (juillet-septembre 1958), séance du 7 juillet 1958, pp. 154-56.

First Known Use

circa 1931, in the meaning defined above

Time Traveler
The first known use of episome was circa 1931

Rhymes for episome

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episome
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Cite this Entry

“Episome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/episome. Accessed 25 Mar. 2025.

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Medical Definition

episome

noun
epi·​some ˈep-ə-ˌsōm How to pronounce episome (audio) -ˌzōm How to pronounce episome (audio)
: a genetic determinant (as the DNA of some bacteriophages) that can replicate either autonomously in bacterial cytoplasm or as an integral part of their chromosomes compare plasmid
episomal
ˌep-ə-ˈsō-məl How to pronounce episome (audio) -ˈzō- How to pronounce episome (audio)
adjective
episomally
-mə-lē How to pronounce episome (audio)
adverb

More from Merriam-Webster on episome

Britannica.com: Encyclopedia article about episome

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