English-language vowel changes before historic /r/

This article contains phonetic transcriptions in the International Phonetic Alphabet (IPA). For an introductory guide on IPA symbols, see Help:IPA. For the distinction between [ ], / / and ⟨ ⟩, see IPA § Brackets and transcription delimiters.

In English, many vowel shifts affect only vowels followed by /r/ in rhotic dialects, or vowels that were historically followed by /r/ that has been elided in non-rhotic dialects. Most of them involve the merging of vowel distinctions and so fewer vowel phonemes occur before /r/ than in other positions of a word.