1398: Mergers and Splits Oct 9, 2018
To describe differences in vowels among accents, people often will describe mergers and splits. A merger is when two sounds that began as distinct in certain context begin to sound the same. For instance, the so called PIN-PEN merger present in Southern American English means that the pronunciation of those two words that are distinct in Standard American English sound the same before a nasal sound. A split has the same effect, but the opposite chronology. The FOOT-STRUT split is now more common than the opposite, wherein the vowel in those two words sounds different, but originally these would have been the same.
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