Definition of exon in English:

exon

noun

Biochemistry
  • A segment of a DNA or RNA molecule containing information coding for a protein or peptide sequence.

    Compare with intron
    • ‘He concluded that recombination had separated the genealogical histories of introns and exons within these genes.’
    • ‘As a result, the protein sequences encoded by these exons are nearly identical between the two species.’
    • ‘Sequence data for each gene encompassed all coding exons and the intervening introns.’
    • ‘The structure of the invertase genes are fairly similar, each containing between six and eight exons.’
    • ‘All of them contained usually short fragments of coding sequences corresponding to exons of single-copy genes.’

Origin

1970s: from expressed (see express) + -on.

Pronunciation:

exon

/ˈeksän/