intron

noun

in·​tron ˈin-ˌträn How to pronounce intron (audio)
: a polynucleotide sequence in a nucleic acid that does not code information for protein synthesis and is removed before translation of messenger RNA compare exon

Examples of intron in a Sentence

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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.
Several mechanisms that could create introns have been identified, and all of them may have contributed some introns to eukaryotes. — Jake Buehler, Quanta Magazine, 30 Mar. 2023 Moreover, the mystery around the origins of introns only deepens in light of the extreme variation in where introns tend to show up throughout the eukaryote tree of life. — Jake Buehler, Quanta Magazine, 30 Mar. 2023

Word History

Etymology

intervening sequence + -on entry 2

First Known Use

1978, in the meaning defined above

Time Traveler
The first known use of intron was in 1978

Browse Nearby Words

intromit
intron
introrse
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Cite this Entry

“Intron.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/intron. Accessed 8 Apr. 2025.

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Medical Definition

intron

noun
in·​tron ˈin-ˌträn How to pronounce intron (audio)
: a polynucleotide sequence in a nucleic acid that does not code information for protein synthesis and is removed before translation of messenger RNA compare exon
intronic
in-ˈträn-ik How to pronounce intron (audio)
adjective

More from Merriam-Webster on intron

Britannica.com: Encyclopedia article about intron

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