Rhotic and non-rhotic accents

Rhoticity in English refers to the situations in which English speakers pronounce the historical rhotic consonant /r/, and is one of the most prominent distinctions by which varieties of English can be classified. The English dialects of Scotland, Ireland, and most of the United States and Canada preserve historical /r/, and are thus termed the rhotic varieties. The non-rhotic varieties, in which historical /r/ has been lost except before vowels, include all the dialects of England—except the South West, the southern West Midlands, and parts of West Lancashire—as well as the English dialects of Australia, New Zealand, South Africa, and some parts of the southern and eastern coastal United States.

In non-rhotic varieties, speakers no longer pronounce /r/ in postvocalic environments – that is, when it is immediately after a vowel and not followed by another vowel. For example, a rhotic English speaker pronounces the words hard and butter as /ˈhɑːrd/ and /ˈbʌtər/, whereas a non-rhotic speaker "drops" or "deletes" the /r/ sound, pronouncing them as /ˈhɑːd/ and /ˈbʌtə/. A non-rhotic speaker usually still pronounces the /r/ in the continuously spoken phrase "butter and jam" (the linking R), since in this case the /r/ is followed by a vowel.

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