from 1539.
smack"heroin," 1942, Amer.Eng. slang, probably an alteration of schmeck "a drug," esp. heroin (1932), from Yiddish schmeck "a sniff."
smack"make a sharp noise with the lips," 1557, probably of imitative origin (see
smack (v.2)). Meaning "a loud kiss" is recorded from 1604. With adverbial force, attested from 1782; extended form smack-dab is attested from 1892, Amer.Eng. colloquial.
smack"single-masted sailboat," 1611, probably from Du. or Low Ger. smak "sailboat," from smakken "to fling, dash" (see
smack (v.2)), perhaps so-called from the sound made by its sails. Fr. semaque, Sp. zumaca, It. semacca probably are Gmc. borrowings.
smack"to slap with the hand," 1835, from noun in this sense (c.1746), perhaps influenced by Low Ger. smacken "to strike, throw," which is likely of imitative origin (cf. Swed. smak "slap," M.L.G. smacken, Fris. smakke, Du. smakken "to fling down," Lith. smagiu "to strike, knock down, whip").