Origin: before 1000; (noun) Middle English smacke,Old English smæc; cognate with Middle Low German smak,German Geschmack taste; (v.) Middle English smacken to perceive by taste, have a (specified) taste, derivative of the noun; compare German schmacken
Origin: 1960–65; probably special use of smack1; compare earlier slang schmeck with same sense (< Yiddish shmek sniff, whiff; compare Middle High German smecken (German schmecken) to taste)
"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").