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Old English fugel "bird," representing the general Germanic word for them, from Proto-Germanic *foglaz (cf. Old Frisian fugel, Old Norse fugl, Middle Dutch voghel, Dutch vogel, German vogel, Gothic fugls), probably by dissimilation from *flug-la-, literally "flyer," from the same root as Old English fleogan, modern fly (v.1).
Originally "bird;" narrower sense of "domestic hen or rooster" (the main modern meaning) is first recorded 1570s; in U.S. also extended to ducks and geese. As a verb, Old English fuglian "to catch birds." Related: Fowled; fowling.