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.
Once purified, the plasmids and enzymes are piped into other tanks, where a biochemical reaction produces the dsRNA. — Byerik Stokstad, science.org, 27 June 2024 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 Enzymes are used to cut the plasmids into linear pieces of DNA that encode the spike protein, and a different enzyme converts that DNA into mRNA. — Tanya Lewis, Scientific American, 4 Jan. 2024 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 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

Rhymes for plasmid

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Browse Nearby Words

-plasmia
plasmid
plasmin
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Cite this Entry

“Plasmid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plasmid. Accessed 7 Jul. 2026.

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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

More from Merriam-Webster on plasmid

Britannica.com: Encyclopedia article about plasmid

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