yourselfyoudaoicibaDictYouDict[yourself 词源字典]
by early 14c., from your + self. Plural yourselves first recorded 1520s.[yourself etymology, yourself origin, 英语词源]
youseyoudaoicibaDictYouDict
dialectal inflection of you, 1876, not always used in plural senses.
youth (n.)youdaoicibaDictYouDict
Old English geoguð "youth; young people, junior warriors; young of cattle," related to geong "young," from Proto-Germanic *jugunthi- (cognates: Old Saxon juguth, Old Frisian jogethe, Middle Dutch joghet, Dutch jeugd, Old High German jugund, German Jugend, Gothic junda "youth"), from suffixed form of PIE root *yeu- "vital force, youthful vigor" (see young (adj.)) + Proto-Germanic abstract noun suffix *-itho (see -th (2)).

According to OED, the Proto-Germanic form apparently was altered from *juwunthiz by influence of its contrast, *dugunthiz "ability" (source of Old English duguð). In Middle English, the medial -g- became a yogh, which then disappeared.
They said that age was truth, and that the young
Marred with wild hopes the peace of slavery
[Shelley]
youthful (adj.)youdaoicibaDictYouDict
1560s, from youth + -ful. Old English had geoguðlic. Other words formerly used in the same sense were youthlike, youthly, youthsome, youthy. Related: Youthfulness.
yowyoudaoicibaDictYouDict
exclamation, with various meanings, mid-15c.
yowl (v.)youdaoicibaDictYouDict
c. 1200, yuhelen, probably of imitative origin. Related: Yowled; yowling. The noun is recorded from mid-15c.
yowzayoudaoicibaDictYouDict
colloquial form of yes, sir, 1934, popularized by U.S. bandleader and radio personality Ben "The Old Maestro" Bernie (1891-1943).
ytterbium (n.)youdaoicibaDictYouDict
metallic rare-earth element, 1879, coined in Modern Latin by Swedish chemist Carl Gustaf Mosander (1797-1858) from Ytterby, name of a town in Sweden where mineral containing it was found.
yttriumyoudaoicibaDictYouDict
metallic rare-earth element, 1866, coined in Modern Latin by Swedish chemist Carl Gustaf Mosander (1797-1858) from Ytterby, name of a town in Sweden where mineral containing it was found.
yuan (n.)youdaoicibaDictYouDict
Chinese unit of currency introduced 1914, from Chinese yuan "round, round object, circle."
YucatanyoudaoicibaDictYouDict
said to be from a local word meaning "massacre." Related: Yucatecan.
yucca (n.)youdaoicibaDictYouDict
Central and South American name for the cassava plant, 1550s, from Spanish yuca, juca (late 15c.), probably from Taino, native language of Haiti.
yuck (1)youdaoicibaDictYouDict
exclamation of disgust, 1966, origin perhaps echoic (compare Newfoundland slang yuck "to vomit," 1963; U.S. slang yuck "despised person," 1943; provincial English yuck "the itch, mange, scabies"). Variant yech is by 1969.
yuck (2)youdaoicibaDictYouDict
"laugh," 1938, yock, probably imitative.
yucky (adj.)youdaoicibaDictYouDict
1970, from yuck (1) + -y (2). Related: Yuckiness.
Yugoslav (n.)youdaoicibaDictYouDict
1853, from Slav + Serbo-Croatian jugo- "south," comb. form of jug "south, south wind, noon," from Old Church Slavonic jugu "south, south wind, noon."
YugoslaviayoudaoicibaDictYouDict
1929 (earlier the country was Kingdom of the Serbs, Croats, and Slovenes); from Yugoslav + -ia. The name vanished from the map in 2003.
yuk (n.)youdaoicibaDictYouDict
"laughter, something evoking laughs," 1964, imitative; see yuck (2).
YukonyoudaoicibaDictYouDict
territory of northwestern Canada, named for the river, from Athabaskan, perhaps Koyukon yookkene or Lower Tanana yookuna, said to mean "big river."
yule (n.)youdaoicibaDictYouDict
Old English geol, geola "Christmas Day, Christmastide," from Old Norse jol (plural), a heathen feast, later taken over by Christianity, of unknown origin.

The Old English (Anglian) cognate giuli was the Anglo-Saxons' name for a two-month midwinter season corresponding to Roman December and January, a time of important feasts but not itself a festival. After conversion to Christianity it narrowed to mean "the 12-day feast of the Nativity" (which began Dec. 25), but was replaced by Christmas by 11c., except in the northeast (areas of Danish settlement), where it remained the usual word.

Revived 19c. by writers to mean "the Christmas of 'Merrie England.' " First direct reference to the Yule log is 17c. Old Norse jol seems to have been borrowed in Old French as jolif, hence Modern French joli "pretty, nice," originally "festive" (see jolly).