mid-15c., "to season (food), add a sauce or relish to," from sauce (n.). By 1510s in the figurative sense of "intermix or accompany with what gives piquancy or relish." From 1862 as "to speak to impertinently, treat with impertinence." Related: Sauced; saucing.
mid-14c., "condiment for meat, fish, etc.; pickling liquid, brine," from Old French sauce, sausse, from Latin salsa "things salted, salt food," noun use of fem. singular or neuter plural of adjective salsus "salted," from past participle of Old Latin sallere "to salt," from sal (genitive salis) "salt" (from PIE root *sal- "salt").
From late 14c. as "a curative preparation, medicinal salt." Often in 15c.-17. sawce, salse; constant reimportation of the word in French cookery terms might have helped keep the older spelling. Also formerly applied broadly in provincial English and U.S. to condiments of any kind, especially garden vegetables or roots eaten with meat (1620s), also known as garden-sauce.
Figurative meaning "something which adds piquancy to words or actions" is recorded from c. 1500; the sense of "impertinence" is by 1835, but the connection of ideas in it is much older (see saucy, and compare sass). Slang meaning "liquor" is attested by 1940. Figurative phrases suggesting "subject to the same kind of usage" is by 1520s (serued with the same sauce).
c. 1500, "resembling sauce" (a sense now obsolete), later, of persons, words, etc., "impertinent in speech or conduct, flippantly bold, cheeky" (1520s), from sauce (n.) + -y (2). The connecting notion is sauce in the figurative sense of "that which adds intensity, piquancy in words or actions."
Compare Skelton's have eaten sauce for "be abusive." Also compare sauce malapert "impertinence" (1520s), and sauce (n.) in its obsolete use as a vocative for "impudent person" (1530s). In Shakespeare, with overtones of "wanton, lascivious," it was "a term of serious condemnation" [OED]. Also compare salty in similar senses.
1846 as a kind of sauce served with meat; 1975 as a kind of dance music; separate borrowings from Spanish, literally "sauce," from Vulgar Latin *salsa "condiment" (see sauce (n.)). In American Spanish it is especially used of a kind of relish with chopped-up ingredients; the music is a "blend" of Latin jazz and rock styles.
"one addicted to making saucy remarks," 1580s, sawcebox; see saucy + box (n.1). There never seems to have been a literal sense in reference to the "condiment" meaning of sauce; a sauce-boat (1733) was a small, lipped vessel for sauces, and compare saucer. A saucery (mid-15c.) was "a place where sauces are made."
