n.
Pronunciation: ' ä-blau ̇ t, ' a-; ' äp- ˌ lau ̇ t
Function: noun
Etymology: German, from about away from + Laut sound
Date: 1849
: a systematic variation of vowels in the same root or affix or in related roots or affixes especially in the Indo-European languages that is usually paralleled by differences in use or meaning (as in sing, sang, sung, song )