Canadian raising

Most commonly, the shift affects /aɪ/ ⓘ or /aʊ/ ⓘ, or both, when they are pronounced before voiceless consonants (therefore, in words like price and clout, respectively, but not in prize and cloud).

In North American English, /aɪ/ and /aʊ/ usually begin in an open vowel [ä~a], but through raising they shift to [ɐ] ⓘ, [ʌ] ⓘ or [ə] ⓘ.

[1] In the U.S., aboot [əˈbut], an exaggerated version of the raised pronunciation of about [əˈbʌʊt], is a stereotype of Canadian English.

A study of three speakers in Meaford, Ontario, showed that pronunciation of the diphthong /aɪ/ fell on a continuum between raised and unraised.

Hence, while in accents without raising, writer and rider are pronounced differently as a result of a slight difference in vowel length due to pre-fortis clipping, in accents with raising, the words may be distinguished by their vowels: writer [ˈɹʌɪɾɚ], rider [ˈɹaɪɾɚ].

In most of Canada, the raised vowel is further front than /aɪ/,[12] and in traditional New York City English, /aɪ/ is backed towards [ɑɪ] except before voiceless consonants, resulting in a distinction based more on frontness,[citation needed] but in Philadelphia it may be more back.

In raised /aʊ/, the first element tends to be farther back in Quebec and the Canadian Prairies and Maritimes (particularly in Alberta): thus, [ʌʊ].

[19] This phenomenon is most consistently found in the Inland North, the Upper Midwest, New England, New York City, and the mid-Atlantic areas of Pennsylvania (including Philadelphia), Maryland, and Delaware, as well as in Virginia.

[15] Raising of /aɪ/ before certain voiced consonants is most prominent in the Inland North, Western New England, and Philadelphia.

Hence, words like tiny, spider, cider, tiger, dinosaur, cyber-, beside, idle (but sometimes not idol), and fire may contain a raised nucleus.

Hence, some researchers have argued that there has been a phonemic split in these dialects; the distribution of the two sounds is becoming more unpredictable among younger speakers.