Great Vowel Shift

American  

noun

Linguistics.

1. a series of changes in the quality of the long vowels between Middle and Modern English as a result of which all were raised, while the high vowels (ē) and (o̅o̅), already at the upper limit, underwent breaking to become the diphthongs (ī) and (ou).

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Great Vowel Shift British  

noun

1. linguistics a phonetic change that took place during the transition from Middle to Modern English, whereby the long vowels were raised: ( eː became iː , oː became uː ), etc. The vowels ( iː ) and ( uː ) underwent breaking and became the diphthongs ( aɪ ) and ( aʊ )

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Example Sentences

Then the Great Vowel Shift happened, and those old spellings and pronunciations suddenly looked obscure.

From Slate

Between about 1400 and 1600, the English language underwent what’s grandly called the Great Vowel Shift.

From Slate

He also bemoans the death of “-exit” as a suffix, which hasn’t been used since June, saying that calling every little thing remotely to do with leaving “something-exit” would have revolutionised the English language, akin to the great vowel shift of the 15th century, and it wouldn’t have become tedious in the slightest.

From The Guardian

And he refers to the Great Vowel Shift — the period between 1400 and 1600 A.D. when pronunciation of the letter A went from “ah” to “ay” and when E morphed from “ay” to “ee,” among other changes — with a reverence some might reserve for the Treaty of Westphalia or the Big Bang.

From Washington Post

Edwards was quite a dramatic host, with a disconcerting drawl that largely dispensed with the letter "R" and had performed its own Great Vowel Shift so that you periodically ended up with sentences like "Mahcus Antony and Octavius effahctively divided the Roman wahld between them" which I must say took some getting used to.

From The Guardian