1508, "resembling sauce," later "impertinent, cheeky" (1530), from sauce (q.v.). The connecting notion is the fig. sense of "piquancy in words or actions." Cf. sauce malapert "impertinence" (1529), and slang phrase to have eaten sauce "be abusive" (1526). Also cf. salty in same senses.
[saws-yey; Fr. soh-sye] 
