"an act of licking," c. 1600, from lick (v.1). The earlier noun was licking (late 14c.; Old English had liccung). The meaning "small portion" is 1814, originally Scottish; hence the U.S. colloquial sense. Sense of "place where an animal goes to lick salt" is from 1747. The jazz music sense of "short figure or solo" is by 1922, perhaps from an earlier colloquial sense "a spurt or brisk run in racing" (1809). Meaning "a smart blow" (1670s) is from lick (v.2).
of light, flame, etc., "flowing or running over the surface," 1640s, from a figurative use of Latin lambentem (nominative lambens), present participle of lambere "to lick, lap, wash, bathe," from PIE root *lab-, indicative of smacking lips or licking (source also of Greek laptein "to sip, to lick," Old English lapian "to lick, lap up, to suck;" see lap (v.1)).
"lick up (liquid), take into the mouth with the tongue," from Old English lapian "to lap up, drink," from Proto-Germanic *lapojan (source also of Old High German laffen "to lick," Old Saxon lepil, Dutch lepel, German Löffel "spoon"), from PIE imitative base *lab- (source also of Greek laptein "to sip, lick," Latin lambere "to lick"), indicative of licking, lapping, smacking lips.
Of water, "splash gently, flow against" first recorded 1823, based on similarity of sound. Figurative use of lap (something) up "receive it eagerly" is by 1890. Related: Lapped; lapping. The noun meaning "liquid food; weak beverage" is from 1560s.
Old English cyssan "to touch with the lips" (in respect, reverence, etc.), from Proto-Germanic *kussjan (source also of Old Saxon kussian, Old Norse kyssa, Old Frisian kessa, Middle Dutch cussen, Dutch, Old High German kussen, German küssen, Norwegian and Danish kysse, Swedish kyssa), from *kuss-, probably ultimately imitative of the sound. Gothic used kukjan. Of two persons, "to reciprocally kiss, to kiss each other," c. 1300. Related: Kissed; kissing. The vowel was uncertain through Middle English; for vowel evolution, see bury.
Kissing, as an expression of affection or love, is unknown among many races, and in the history of mankind seems to be a late substitute for the more primitive rubbing of noses, sniffing, and licking. The partial agreement among some words for 'kiss' in some of the IE languages rests only on some common expressive syllables, and is no conclusive evidence that kissing was known in IE times. [Carl Darling Buck, "A Dictionary of Selected Synonyms in the Principal Indo-European Languages," 1949]
A common ku- sound may be found in the Germanic root and Greek kynein "to kiss," Hittite kuwash-anzi "they kiss," Sanskrit cumbati "he kisses." Some languages make a distinction between the kiss of affection and that of erotic love (compare Latin saviari "erotic kiss," vs. osculum, literally "little mouth"). French embrasser "kiss," but literally "embrace," came about in 17c. when the older word baiser (from Latin basiare) acquired an obscene connotation.
To kiss the cup "drink liquor" is early 15c. To kiss the dust "die" is from 1835. To kiss and tell is from 1690s. Figurative (and often ironic) kiss (something) goodbye is from 1935. To kiss (someone) off "dismiss, get rid of" is from 1935, originally of the opposite sex. Insulting invitation kiss my arse (or ass) as an expression of contemptuous rejection is from at least 1705, but probably much older (see "The Miller's Tale").