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

"Together, these findings reveal a direct molecular link between synonymous codon choice and the control of gene expression in human cells," says co-corresponding author Masanori Yoshinaga.

From Science Daily • Apr. 9, 2026

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

It treats a particular three letter sequence, typically a stop codon that marks the end of a protein, in two different ways.

From Science Daily • Feb. 28, 2026

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

From Textbooks • Apr. 25, 2013

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

From Textbooks • Apr. 25, 2013