In English, the Ottoman sultan was the Grand Turk (late 15c.), and the Turk was used collectively for the Turkish people or for Ottoman power (late 15c.). From 14c. and especially 16c.-18c. Turk could mean "a Muslim," reflecting the Turkish political power's status in the Western mind as the Muslim nation par excellence. Hence Turkery "Islam" (1580s); turn Turk "convert to Islam."
Meaning "person of Irish descent" is first recorded 1914 in U.S., apparently originating among Irish-Americans; of unknown origin (Irish torc "boar, hog" has been suggested). Young Turk (1908) was a member of an early 20c. political group in the Ottoman Empire that sought rejuvenation of the Turkish nation. Turkish bath is attested from 1640s; Turkish delight from 1877.
Old English geong "youthful, young; recent, new, fresh," from Proto-Germanic *junga- (source also of Old Saxon and Old Frisian jung, Old Norse ungr, Middle Dutch jonc, Dutch jong, Old High German and German jung, Gothic juggs), from PIE *yuwn-ko-, suffixed form of root *yeu- "vital force, youthful vigor" (source also of Sanskrit yuvan- "young; young man;" Avestan yuuanem, yunam "youth," yoista- "youngest;" Latin juvenis "young," iunior "younger, more young;" Lithuanian jaunas, Old Church Slavonic junu, Russian junyj "young," Old Irish oac, Welsh ieuanc "young").
From c. 1830-1850, Young France, Young Italy, etc., were loosely applied to "republican agitators" in various monarchies; also, especially in Young England, Young America, used generally for "typical young person of the nation." For Young Turk, see Turk.
1792, "an Ottoman Turk," especially a member of the ruling dynasty; as an adjective by 1829, "relating to the empire of Turkey," from Turkish Osmanli "of or pertaining to Osman," founder of the Ottoman dynasty (he reigned 1259-1326); his name is the Turkish pronunciation of Arabic Uthman. This is the native word where English generally uses Ottoman. In early use as a noun in English often mistakenly regarded as a plural.
It was the typical name in the North and the Northern armies for a Confederate soldier during the American Civil War, and the Southern soldiers were, collectively Johnnies, generically Johnny Reb. In the Mediterranean, it was a typical name for an Englishman by c. 1800. In the Crimean War it became the typical name among the English for "a Turk" (also Johnny Turk), later it was extended to Arabs; by World War II the Arabs were using Johnny as the typical name for "a British man"). Johnny Crapaud as a derogatory generic name for a Frenchman or France is from 1818.
Johnny-come-lately "a new arrival" first attested 1839. Johnny-on-the-spot is from 1896. Johnny-jump-up as an American English name for the pansy is from 1837. Johnny-cocks, a colloquial name for the early purple orchid (Orchis mascula) is attested from 1883.
"tedious and ineffectual person," 1935, American English carnival slang, of uncertain origin. Perhaps from jerkwater "petty, inferior, insignificant" [Barnhart, OED]; alternatively from, or influenced by, verbal phrase jerk off "masturbate" [Rawson]. The lyric in "Big Rock Candy Mountain," sometimes offered as evidence of earlier use, apparently is "Where they hung the Turk [not jerk] that invented work."
A soda-jerk (1915; soda-jerker is from 1883) is so called for the pulling motion required to work the taps.
The SODA-FOUNTAIN CLERK
Consider now the meek and humble soda-fountain clerk,
Who draweth off the moistened air with nimble turn and jerk,
[etc., Bulletin of Pharmacy, August, 1902]