: a specific sequence of three consecutive nucleotides that is part of the genetic code and that specifies a particular amino acid in a protein or starts or stops protein synthesis
called also triplet
Examples of codon in a Sentence
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Next, three sets of those letters (called codons) work together to form one of 20 amino acids.
—
Paul Smaglik, Discover Magazine, 23 Jan. 2025
The amino acid glycine is encoded by four different codons (GGU, GGC, GGA, and GGG), the amino acid leucine is encoded by six different codons, and so forth.
—IEEE Spectrum, 14 Oct. 2021
And guess what this codon can do?
—Bruce Y. Lee, Forbes, 5 Jan. 2022
Each codon provides instructions for creating a specific amino acid.
—Jonathon Keats, Discover Magazine, 11 June 2017
Notice that the change is fixed upon the third position in the codon.
—Razib Khan, Discover Magazine, 11 July 2013
Every three consecutive nucleotides in this chain can constitute what’s called a codon.
—Bruce Y. Lee, Forbes, 5 Jan. 2022
One way that viruses adapt is by encoding proteins using the same choice of codons as their host.
—David Cyranoski, Scientific American, 23 Jan. 2020
One way is using genetic data to look at codons—triplets of DNA or RNA letters that are the instructions for making proteins.
—Megan Molteni, Wired, 23 Jan. 2020
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Paul Smaglik, Discover Magazine, 23 Jan. 2025
The amino acid glycine is encoded by four different codons (GGU, GGC, GGA, and GGG), the amino acid leucine is encoded by six different codons, and so forth.
—IEEE Spectrum, 14 Oct. 2021
And guess what this codon can do?
—Bruce Y. Lee, Forbes, 5 Jan. 2022
Each codon provides instructions for creating a specific amino acid.
—Jonathon Keats, Discover Magazine, 11 June 2017
Notice that the change is fixed upon the third position in the codon.
—Razib Khan, Discover Magazine, 11 July 2013
Every three consecutive nucleotides in this chain can constitute what’s called a codon.
—Bruce Y. Lee, Forbes, 5 Jan. 2022
One way that viruses adapt is by encoding proteins using the same choice of codons as their host.
—David Cyranoski, Scientific American, 23 Jan. 2020
One way is using genetic data to look at codons—triplets of DNA or RNA letters that are the instructions for making proteins.
—Megan Molteni, Wired, 23 Jan. 2020
Cite this Entry
“Codon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/codon. Accessed 23 Jul. 2025.
Copy CitationMedical Definition
codon
noun
co·don
ˈkō-ˌdän 
: a specific sequence of three consecutive nucleotides that is part of the genetic code and that specifies a particular amino acid in a protein or starts or stops protein synthesis
called also triplet
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