North American English regional phonology

North American English regional phonology is the study of variations in the pronunciation of spoken North American English (English of the United States and Canada), though studies of regional dialects can be based on multiple factors, including phonological (abstract sound-based), phonetic (physical sound-based), lexical (vocabulary-based), and some syntactic (grammar-based) factors. North American English includes American English, which has several highly developed and distinct regional varieties, along with the closely related Canadian English, which is more homogeneous. American English (especially Western dialects) and Canadian English have more in common with each other than with varieties of English outside North America.

The most recent work documenting and studying the phonology of North American English dialects as a whole is the 2006 Atlas of North American English (ANAE) by William Labov, Sharon Ash, and Charles Boberg, on which much of the description below is based, following on a tradition of sociolinguistics dating to the 1960s; earlier large-scale American dialectology focused more on lexicology than on phonology.

Regional dialects in North America are historically the most strongly differentiated along the Eastern seaboard, due to distinctive speech patterns of urban centers of the American East Coast like Boston, New York City, and certain Southern cities, all of these accents historically noted by their London-like r-dropping (called non-rhoticity), a feature gradually receding among younger generations, especially in the South. The Connecticut River is now regarded as the southern and western boundary of the traditional New England accents, today still centered on Boston and much of Eastern New England. The Potomac River generally divides a group of Northeastern coastal dialects from an area of older Southeastern coastal dialects. All older Southern dialects, however, have mostly now receded in favor of a strongly rhotic, more unified accent group spread throughout the entire Southern United States since the late 1800s and into the early 1900s. In-between the two aforementioned rivers, some other variations exist, most famous among them being New York City English.

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