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ablaut

American  
[ahb-lout, ab-, ahp-lout] / ˈɑb laʊt, ˈæb-, ˈɑp laʊt /

noun

Grammar.
  1. (in Indo-European languages) regular alternation in the internal phonological structure of a word element, especially alternation of a vowel, that is coordinated with a change in grammatical function or combination, as in English sing, sang, sung, song; apophony.


ablaut British  
/ ˈaplaut, ˈæblaʊt /

noun

  1. linguistics vowel gradation, esp in Indo-European languages See gradation

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of ablaut

1840–50; < German, equivalent to ab- off + Laut sound

Explanation

Ablaut is a linguistic term that refers to the changing of vowel sounds within a word to indicate a shift in grammatical function, like in drive, drove, and driven. While most modern English verbs simply add -ed to the end of a word to make it past tense — such that walk becomes walked and had walked — other English verbs are irregular: e.g., take, took, and taken. This is due to ablaut, which dates back thousands of years to Proto-Indo-European, the common ancestor of English, Latin, Greek, and Sanskrit. In Indo-European languages, such variation of vowels to indicate changes in tense or number is common, and it remains in English for some verbs, like sing, sang, and sung. The term ablaut originates from the German words ab, meaning "off," and laut, meaning "sound."

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

According to the New English Dictionary, “grub” may be referred to an ablaut variant of the Old Teutonic grab-, to dig, cf. “grave.”

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 6 "Groups, Theory of" to "Gwyniad" by Various

By ablaut is meant the gradation of vowels both in stem and suffix, which was chiefly caused by the primitive Indo-Germanic system of accentuation.

From A Middle High German Primer Third Edition by Wright, Joseph