codon

American

[koh-don] / ˈkoʊ dɒn /

noun

Genetics.

a triplet of adjacent nucleotides in the messenger RNA chain that codes for a specific amino acid in the synthesis of a protein molecule.

codon British

/ ˈkəʊdɒn /

noun

genetics biochem a unit that consists of three adjacent bases on a DNA molecule and that determines the position of a specific amino acid in a protein molecule during protein synthesis

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

codon Scientific

/ kō′dŏn′ /

A sequence of three adjacent nucleotides on a strand of a nucleic acid (such as DNA) that constitutes the genetic code for a specific amino acid that is to be added to a polypeptide chain during protein synthesis. Some amino acids are coded for by more than one codon, and some codons do not signal a particular amino acid but rather signal a stop to protein synthesis.

codon Cultural

A group of three bases on the DNA molecule. Each codon determines the identity of one amino acid in proteins made by the cell.

Etymology

Origin of codon

An Americanism dating back to 1960–65; code + -on ¹

Compare meaning

How does codon compare to similar and commonly confused words? Explore the most common comparisons:

codon vs. anticodon

Vocabulary lists containing codon

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Example Sentences

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See Examples For:

codon

These findings change how scientists think about gene regulation, showing that codon choice itself plays a direct role in controlling gene expression in human cells.

From Science Daily ● Apr. 9, 2026

In nearly all organisms studied so far, every three letter codon either specifies one particular amino acid or signals the end of a protein.

From Science Daily ● Feb. 28, 2026

PL0344, only TGA functions as a stop codon -- although Dr McGowan found there are more TGA codons than expected in the ciliate's DNA, believed to compensate for the loss of the other two.

From Science Daily ● Oct. 5, 2023

The relationship between a nucleotide codon and its corresponding amino acid is called the genetic code.

From Textbooks ● Apr. 25, 2013

The genetic code is the correspondence between the three-nucleotide mRNA codon and an amino acid.

From Textbooks ● Apr. 25, 2013

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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023