Origin and history of lop

Old English læppa (plural læppan) "skirt or flap of a garment," from Proto-Germanic *lapp- (source also of Old Frisian lappa, Old Saxon lappo, Middle Dutch lappe, Dutch lap, Old High German lappa, German Lappen "rag, shred," Old Norse leppr "patch, rag"), of uncertain origin.

Sense of "lower front part of a shirt or skirt" led to that of "upper legs of seated person" (c. 1300). Used figuratively ("bosom, breast, place where someone or something is held and cherished") from late 14c., as in lap of luxury (which is first recorded 1802). To drop or dump something in someone's lap "shift a burden" is from 1962. From 15c.-17c. the word (often in plural) was a euphemism for "female pudendum," but this is not the source of lap dance, which is first recorded 1993.

To lap dance, you undress, sit your client down, order him to stay still and fully clothed, then hover over him, making a motion that you have perfected by watching Mister Softee ice cream dispensers. [Anthony Lane, review of "Showgirls," New Yorker, Oct. 16, 1995]

Lap-clap was old slang for "an act of coition" (c. 1600), in warning expressions to youth often paired with lip-clip "a kiss." Also compare slang Lapland "the society of women."

"send up in a slow, high arc," 1869, of artillery shells; 1875 of tennis strokes, of uncertain origin, perhaps somehow from some sense in lob (n.). Earlier the verb meant "to throw slowly or gently" in bowling (1824) Related: Lobbed; lobbing. The noun in the "high, arcing throw or hit" sense (originally in tennis) is from 1875, from the verb.

also lop-sided, "leaning to one side as a result of being disproportionately balanced," 1711 (lapsided), first used of ships; from lop (v.2) + side (n.). Related: Lopsidedly; lopsidedness.