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plasmid

noun

plas·​mid ˈplaz-məd How to pronounce plasmid (audio)
: an extrachromosomal ring of DNA especially of bacteria that replicates autonomously

Examples of plasmid 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.
In RenBio’s case, the researchers spelled out the instructions to make a GLP-1 receptor agonist protein — essentially the same active ingredient in medicines like Ozempic and Mounjaro — and looped it into a small circle called a plasmid. Brenda Goodman, CNN Money, 4 Nov. 2025 Han was accused of smuggling in filter paper containing plasmids on Sept. 23 and March 5 and petri dishes containg C. elegans with genetic modifications on Sept. 29, according to an information filed in court June 26. Christina Hall, Freep.com, 19 Aug. 2025 Through the not-for-profit plasmid repository Addgene, PROTEUS will be available to any lab worldwide with the appropriate infrastructure, virology training, and skills in molecular biology. IEEE Spectrum, 27 July 2025 The strain also carried a separate genetic element (a plasmid) that provided resistance mechanisms against streptomycin and spectinomycin, cephalosporins, macrolides, and sulphonamides. Beth Mole, ArsTechnica, 11 Apr. 2025 See All Example Sentences for plasmid

Word History

Etymology

plasma + -id entry 2

First Known Use

1952, in the meaning defined above

Time Traveler
The first known use of plasmid was in 1952

Browse Nearby Words

Cite this Entry

“Plasmid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plasmid. Accessed 27 Nov. 2025.

Medical Definition

plasmid

noun
plas·​mid ˈplaz-məd How to pronounce plasmid (audio)
: an extrachromosomal ring of DNA that replicates autonomously and is found especially in bacteria compare episome

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