1542 (n.), 1560 (v.), from M.Fr. saillie "a rushing forth," noun use of fem. pp. of saillir "to leap," from L. salire "to leap" (see salient).
fem. proper name, alteration of Sarah (cf. Hal from Harry, Moll from Mary, etc.). Sally Lunn cakes (1780) supposedly named for the woman in Bath who first made them. Sally Ann as a nickname for Salvation Army is recorded from 1927.