英语词源字典 - 在线词源网站

chameleon (n.): mid-14c., camelion, from Old French caméléon, from Latin chamaeleon, from Greek khamaileon "the chameleon," from khamai "on the ground" (also "dwarf"), akin to chthon "earth" (see chthonic) + leon "lion" (see lion). Perhaps the large head-crest on some species was thought to resemble a lion's mane. The classical -h- was restored in English early 18c. Figurative sense of "variable person" is 1580s. It formerly was supposed to live on air (as in "Hamlet" III.ii.98).
dividend (n.): late 15c., from Middle French dividende "a number divided by another," from Latin dividendum "thing to be divided," neuter gerundive of dividere (see divide). Mathematical sense is from 1540s. Meaning "portion of interest on a loan, stock, etc." is from 1620s. Related: Dividends.
float (v.): late Old English flotian "to rest on the surface of water" (intransitive; class II strong verb; past tense fleat, past participle floten), from Proto-Germanic *flotan "to float" (cognates: Old Norse flota, Middle Dutch vloten, Old High German flozzan, German flössen), from *flot-, from PIE *pleud-, extended form of root *pleu- "to flow" (see pluvial).

Meaning "drift about, hover passively" is from c. 1300. Transitive sense of "to lift up, cause to float" (of water, etc.) is from c. 1600; that of "set (something) afloat" is from 1778 (originally of financial operations). Of motion through air, from 1630s. Meaning "hover dimly before the eyes" is from 1775. Related: Floated; floating. A floating rib (by 1802) is so called because the anterior ends are not connected to the rest.
incubation (n.): 1610s, "brooding," from Latin incubationem (nominative incubatio) "a laying upon eggs," noun of action from past participle stem of incubare "to hatch," literally "to lie on, rest on," from in- "on" (see in- (2)) + cubare "to lie" (see cubicle). The literal sense of "sitting on eggs to hatch them" first recorded in English 1640s.
perch (n.1): "where a bird rests," late 13c., originally only "a pole, rod, stick, stake," from Old French perche "unit of linear measurement" (5.5 yards), also "measuring rod, pole, bar" used to measure this length (13c.), from Latin pertica "pole, long staff, measuring rod," related to Oscan perek "pole," Umbrian perkaf "twigs, rods." Meaning "a bar fixed horizontally for a hawk or tame bird to rest on" is attested from late 14c.; this led to general sense of "any thing that any bird alights or rests on" (late 15c.). Figurative sense of "an elevated or secure position" is recorded from 1520s. The "land-measuring rod" sense also was in Middle English (c. 1200), hence surviving meaning "measure of land equal to a square lineal perch" (usually 160 to the acre), mid-15c.
touch (v.): late 13c., "make deliberate physical contact with," from Old French tochier "to touch, hit, knock; mention, deal with" (11c., Modern French toucher), from Vulgar Latin *toccare "to knock, strike" as a bell (source also of Spanish tocar, Italian toccare), perhaps of imitative origin. Related: Touched; touching.

From c. 1300 in transitive sense "bring into physical contact," also "pertain to." Other senses attested from 14c. are "perceive by physical contact, examine by sense of touch," also "be or come into physical contact with; come to rest on; border on, be contiguous with;" also "use the sense of touch," and "mention, describe." From early 14c. as "affect or move mentally or emotionally," with notion of to "touch" the heart or mind. Also from early 14c. as "have sexual contact with." Meaning "to get or borrow money" first recorded 1760. Touch-and-go (adj.) is recorded from 1812, apparently from the name of a tag-like game, first recorded 1650s. Touch football is first attested 1933. Touch-me-not (1590s) translates Latin noli-me-tangere.
tuft (n.): "bunch of soft and flexible things fixed at the base with the upper ends loose," late 14c., of uncertain origin, perhaps from Old French touffe "tuft of hair" (14c.), which is either from Late Latin tufa "a kind of crest on a helmet" (also found in Late Greek toupha), or from a Germanic source (compare Old High German zopf, Old Norse toppr "tuft, summit;" see top (n.1)). As a verb from 1530s. Related: Tufted.