A small bird (Passer domesticus) native to the Old World but widely naturalized elsewhere, having brown and gray plumage with a black throat in the adult male. Also called English sparrow. or English sparrow One of the world's best-known and most abundant small birds (Passer domesticus, family Passeridae or Ploceidae). It lives in towns and on farms worldwide, having accompanied Europeans from its original home in Eurasia and northern Africa. Introduced into North America in 1852, it spread across the continent within a century. It is about 6 in. (15 cm) long and buffy-brown; the male has a black bib. House sparrows breed nearly year-round in warm regions. See also sparrow