Philadelphia English

Philadelphia English is a variety or dialect of American English native to Philadelphia and extending into Philadelphia's suburbs in the Delaware Valley. The Philadelphia accent is one of the best-studied in American English, as Philadelphia's University of Pennsylvania is the home institution of pioneering sociolinguist William Labov. The Philadelphia accent is considered by some to be the most distinctive accent in North America. The mid-twentieth century Philadelphia accent is very similar to the Baltimore accent; in fact, the local varieties of the two cities together constitute what Labov describes as a single "Mid-Atlantic dialect". Philadelphia English also shares some distinct features with New York City English and Midland American English, although it is still its own unique dialect.

According to linguist Barbara Johnstone, migration patterns and geography affected the dialect's development, which was especially influenced by immigrants from Northern England, Scotland, and Northern Ireland. The accent is commonly found within the Irish American and Italian American working class neighborhoods.

Philadelphia English and New York City English had a common ancestor dialect that likely existed in the 1800s. Both modern dialects demonstrate a high /ɔː/ vowel (creating a contrast between words like cot and caught) as well as a phonemic split of the short a vowel, /æ/ (making gas and gap, for example, have different vowels sounds). One important indicator of this is that Philadelphia's short a split is documented as being a simplified variant of New York City's split. Unlike New York City English, however, most speakers of Philadelphia English have always used a rhotic accent (meaning that the r sound is never "dropped").

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