Yo (greeting)

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Yo is a slang interjection, commonly associated with North American English and Philadelphia English. It was popularized by Italian Americans in Philadelphia during the 1940s. Although often used as a greeting and often deployed at the beginning of a sentence, yo may also come at the end of a sentence and/or may be used to place emphasis on or to direct focus onto a particular individual, group, or issue at hand, or to gain the attention of another individual or group. It may also be used to express emotions such as; excitement, surprise, disbelief, enthusiasm, anger, or amazement.

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