Online Etymology Dictionary

lawn mower: also lawn-mower, 1869, from lawn + mower (see mow (v.)).
lawn (2): "thin linen or cotton cloth," 1416, from Laon, city in northern France, center of linen manufacture. The town name is O.Fr. Lan, from L. Laudunum, of Celtic origin.
lawn (1): "turf, stretch of grass," 1548, laune "glade, open space between woods," from M.E. launde, from O.Fr. lande "heath, moor," from Gaul. (cf. Breton lann "heath"), or from its Gmc. cognate, source of Eng. land (q.v.). The -d perhaps mistaken for an affix and dropped. Sense of "mowed grassy ground" first recorded 1733.
edging: 1570s, "the putting of a border," from edge. Meaning "a border" is from 1660s; that of "the trimming of lawn edges" is from 1858.
fescue: 1513, "pointer," from O.Fr. festue, a kind of straw, from L. festuca "straw, stalk, rod," probably related to ferula (see ferule). Sense of "pasture, lawn grass" is first recorded 1762.
Adirondack: type of lawn or deck chair, said to have been designed in 1903 by Thomas Lee, owner of the Westport Mountain Spring, a resort in the Adirondack region of New York State, and commercially manufactured the following year, but said originally to have been called Westport chair after the town where it was first made. Adirondack Mountains is a back-formation from Adirondacks, treated as a plural noun but really from Mohawk (Iroquoian) adiro:daks "tree-eaters," a name applied to neighboring Algonquian tribes, in which the -s is an imperfective affix.
scan (v.): late 14c., "mark off verse in metric feet," from L.L. scandere "to scan verse," originally, in classical L., "to climb" (the connecting notion is of the rising and falling rhythm of poetry), from PIE *skand- "to spring, leap" (cf. Skt. skandati "hastens, leaps, jumps;" Gk. skandalon "stumbling block;" M.Ir. sescaind "he sprang, jumped," sceinm "a bound, jump"). Missing -d in English is probably from confusion with suffix -ed (see lawn (1)). Sense of "look at closely, examine" first recorded 1540s. The (opposite) sense of "look over quickly, skim" is first attested 1926. The noun is recorded from 1706. Scanner as a type of mechanical device is recorded from 1927.
kill (v.): c.1200, "to strike, hit, beat, knock." Sense of "to deprive of life" first recorded early 14c. Perhaps from an unrecorded variant of O.E. cwellan "to kill" (see quell), but the earliest sense suggests otherwise. The noun meaning "an act of killing (an animal)" is from 1852. Lawn tennis serve sense is from 1903. The kill "the knockout" is boxing jargon, 1950. Killer in slang sense of "impressive person or thing" first recorded 1937; as an adj., 1979. Killjoy is first recorded 1776; formerly used with other stems (cf. kill-courtesy "boorish person," kill-cow "bully, big man," etc.). Sense in to kill time is from 1728. Killer whale is from 1725. Killing "large profit" is 1888, Amer.Eng. slang. Kill-devil, colloquial for "rum," especially if new or of bad quality, is from 1630s.
tennis: 1345, most likely from Anglo-Fr. tenetz "hold! receive! take!," from O.Fr. tenez, imperative of tenir "to hold, receive, take," which was used as a call from the server to his opponent. The original version of the game (a favorite sport of medieval Fr. knights) was played by striking the ball with the palm of the hand, and in O.Fr. was called la paulme, lit. "the palm," but to an onlooker the service cry would naturally seem to identify the game. The use of the word for the modern game is from 1874, short for lawn tennis, which originally was called sphairistike (1873), from Gk. sphairistike (tekhne) "(skill) in playing at ball," from the root of sphere. It was invented, and named, by Maj. Walter C. Wingfield and first played at a garden party in Wales, inspired by the popularity of badminton.
"The name 'sphairistike,' however, was impossible (if only because people would pronounce it as a word of three syllables to rhyme with 'pike') and it was soon rechristened." ["Times" of London, June 10, 1927]