codon

American  

[koh-don] / ˈkoʊ dɒn /

noun

Genetics.

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

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codon British  

/ ˈkəʊdɒn /

noun

1. 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

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codon Scientific  

/ kō′dŏn′ /

1. 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.

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codon Cultural  

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

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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

Example Sentences

See Examples For:

codon

PL0344, only TGA appears to function as a stop codon.

From Science Daily ● May 7, 2026

"The UAG codon is like a fork in the road, where it can be interpreted either as a stop codon or as a pyrrolysine residue," Shalvarjian said.

From Science Daily ● Feb. 28, 2026

Researchers had assumed that these organisms simply reassigned the UAG stop codon to represent pyrrolysine.

From Science Daily ● Feb. 28, 2026

Each amino acid is defined by a three- nucleotide sequence called the triplet codon.

From Textbooks ● Apr. 25, 2013

The genetic code is “translated” by the tRNA molecules, which associate a specific codon with a specific amino acid.

From Textbooks ● Apr. 25, 2013