Medical Definition of stop codon
: a genetic codon in messenger RNA that signals the termination of protein synthesis during translation Each codon stands for one of the 20 amino acids that make up proteins or for one of three stop codons that signal the end of a protein chain.—Tina Hesman, Science News, 3 June 2000—called also termination codon; compare start codon
Seen and Heard
What made you want to look up stop codon? Please tell us where you read or heard it (including the quote, if possible).