Definition of sparrow
1
: any of a genus (Passer of the family Passeridae) of small chiefly brownish or grayish Old World oscine songbirds that include some which have been widely introduced;
especially
: house sparrow
2
: any of numerous finches (family Emberizidae) that are New World birds (such as the song sparrow or tree sparrow) resembling the Old World sparrows
