Definition of vowel harmony in English:

vowel harmony

noun

  • [mass noun] The phenomenon in some languages, e.g. Turkish, for all the vowels in a word to be members of the same subclass, for example all front vowels or all back vowels.

    • ‘In Turkish, with its extensive system of vowel harmony, the above categories are more salient than they are in English, for example.’
    • ‘Vowel harmony is probably the most widely known phonological characteristic of Turkic languages.’
    • ‘The phenomenon of vowel harmony has attracted considerable attention among phonologists from all theoretical denominations ever since.’