mammothyoudaoicibaDictYouDict[mammoth 词源字典]
mammoth: [18] Mammoth is a Russian contribution to English. The word was borrowed from early modern Russian mammot, an adaptation of Tatar mamont ‘earth’ (the reason for the animal being so named is that the first remains of mammoths to be found were dug out of the frozen soil of Siberia). The adjectival use of the word for ‘huge’ dates from the early 19th century (‘The dancing very bad; the performers all had mammoth legs’, private diary of Sir Robert Wilson, 1814).
[mammoth etymology, mammoth origin, 英语词源]
fly (n.)youdaoicibaDictYouDict
Old English fleoge "a fly, winged insect," from Proto-Germanic *fleugon "flying insect" (cognates: Old Saxon fleiga, Old Norse fluga, Middle Dutch vlieghe, Dutch vlieg, Old High German flioga, German Fliege "fly"); literally "the flying (insect)" (compare Old English fleogende "flying"), from same source as fly (v.1).

Originally any winged insect (moths, gnats, beetles, locusts, hence butterfly, etc.) and long used by farmers and gardeners for any insect parasite. Flies figuratively for "large numbers" of anything is from 1590s. Plural flien (as in oxen, etc.) gradually normalized 13c.-15c. to -s. Fly in the ointment is from Eccles. x:1. Fly on the wall "unseen observer" first recorded 1881. No flies on _____ "no lack of activity or alertness on the part of," is attested by 1866. Meaning "fish-hook dressed to resemble an insect" is from 1580s; Fly-fishing is from 1650s. Fly-catcher "bird which eats insects on the wing" is from 1670s. The fly agaric mushroom (1788) so called because it was used as a poison for flies.

The sense of "a flight, flying" is from mid-15c. From the verb and the notion of "flapping as a wing does" comes the noun sense of "tent flap" (1810), which was extended to "strip of material sewn into a garment as a covering for buttons" or some other purpose (1844). Baseball fly ball attested by 1866. To do something on the fly is 1856, apparently from baseball.
When the catcher sees several fielders running to catch a ball, he should name the one he thinks surest to take it, when the others should not strive to catch the ball on the fly, but only, in case of its being missed, take it on the bound. ["The American Boys Book of Sports and Games," New York, 1864]
Lepidoptera (n.)youdaoicibaDictYouDict
1773, "insects with four scaly wings," the biological classification that includes butterflies and moths, coined 1735 in Modern Latin by Swedish botanist Carolus Linnaeus (Karl von Linné, 1707-1778) from Greek lepido-, comb. form of lepis (genitive lepidos) "(fish) scale" (related to lepein "to peel;" see leper) + pteron "wing, feather" (see pterodactyl).
mothball (n.)youdaoicibaDictYouDict
also moth-ball, moth ball, "naphthalene ball stored among fabrics to keep off moths," 1891, from moth + ball (n.1).
wormwood (n.)youdaoicibaDictYouDict
c. 1400, folk etymology of Old English wermod "wormwood, absinthe," related to vermouth, but the ultimate etymology is unknown. Compare Old Saxon wermoda, Dutch wermoet, Old High German werimuota, German Wermut. Weekley suggests wer "man" + mod "courage," from its early use as an aphrodisiac. Figurative use, however, is usually in reference to its proverbial bitter aftertaste. Perhaps because of the folk etymology, it formerly was used to protect clothes and bedding from moths and fleas. "A medecyne for an hawke that hath mites. Take the Iuce of wormewode and put it ther thay be and thei shall dye." ["Book of St. Albans," 1486]