Alternation in the vowels of related word forms, especially in Germanic strong verbs (e.g. in sing, sang, sung)
as modifier‘an ablaut series’
‘When ablaut is a regular feature of a language's grammar, it is often called vowel gradation.’
‘It is the relationship between phonemic pitch and the nature of ablaut in standard Lithuanian which makes this clear.’
‘You can't even distinguish between the preterite and participle Germanic ablauts of English.’
‘There are various categories of this: rhyming, exact and ablaut (vowel substitution).’
‘The Proto-Indo-European phonetics was not stable at all: ablauts (vowel interchanges), assimilations, many different consonant processes at the end of the word.’
Origin
Mid 19th century from German, from ab ‘off’ + Laut ‘sound’.
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