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Language spoken by felons, thieves, knaves, and vagabonds; cant; slang. "In a wild district of Derbyshire, between Macclesfield and Buxton, there is a village called Flash, surrounded by uninclosed land. The squatters on these commons, with their wild gipsey habits, travelled about the neighborhood from fair to fair, using a slang dialect of their own. They were called the Flash men, and their dialect Flash talk; and it is not difficult to see the stages by which the word Flash has reached its present signification."-Isaac Taylor.