Green’s Dictionary of Slang

1. (Anglo-Ind., also ramjony, Ram Johnny) an Indian man who attached himself to a newly arrived colonial, offering help and expecting recompense; also attrib. [apparently an alteration of the personal name Ramazani].

1796		J. Gilchrist Grammar of Hindoostanee Lang. 177: [W]hence the well known corruption, sik-man, so useful to the taza wilautees, when any thing gets out of order, as the Ramjonies make no bones of calling a bullock, cart, boat, &c. sikman!
1810		T. Williamson East India Vade-Mecum I 191: [T]he present banians, who attach themselves to captains of European ships, may, without the least hazard of controversion, be considered as nothing more or less than Rum-Johnnies‘of a larger growth’.
1825		J.B. Gilchrist General East India and Vade Mecum 84: The disreputable circumstance of having a thief at his elbow, does not sit very easy on the stranger’s mind: deriving so much convenience from Rum Johnny’s aid, and, having only the fair side of the knave’s conduct in view, be is unwilling to give credit to what appears a gross misrepresentation, founded on prejudice.
1828		[C. D’Oyly] Tom Raw, the Griffin 28: Ram-Johnnies are blood-suckers, arrant leeches, / Discarded servants, exhibitioners, / Always prepared, with broken English speeches, / To act as tongue to new and raw practitioners / [...] / Premeditated rogues, established hummers. / Who prowl round Ghauts, the houses of provisioners / And taverns, ready to entrap new comers.
1837		F.J. Shore Notes on Indian Affair II 318: On the other hand, on their first landing in India, they are surrounded by a set of scamps who are known by the cant name of Rum Johnnies: (a corruption of the Moosulman name Rumzanee, which is commonly given to boys born during the Rumzan or Lent) .
1844		Peregrine Pultuney II 28: He put to flight a small detachment of Rum Johnnies, who were [...] offering their services most obsequiously to the griffins, fawning and salaaming with all their might. [footnote: Rum Johnnies are low native servants out of place, who speak a little English, frequent the ghauts of Calcutta, and prey on the griffins].
1874		J. Grant Fairer Than a Fairy II 14: ‘[H]ence a description of the holder should always be appended, to prevent these Rum Johnnies from imposing upon us.’ [...] The servants, too, were of the Rum-Johnny order – a dissolute, dirty set of Mahomedans, whom I have before described – those usually picked up by young officers on account of their speaking the English language.
1886		Yule & Burnell Hobson-Jobson 584/2: Rum-johnny, s. Two distinct meanings are ascribed to this vulgar word, both we believe, obsolete. (a). It was applied [...] to a low classof native servants who plied on the wharves of Calcutta in order to obtain employment from new-comers.

2. (Anglo-Ind., also Ramjanny, ramjannee, Ramjohnny) a dancing-girl, especially one that also practiced prostitution; a prostitute [Hind. ?????? (r?mjan?) a prostitute].

1810		B. Solvyns Les Hindoûs II n.p.: The dance is generally executed by three female dancers or Ramjannys, who are courtesans as well as Bayaderes.
1813		J. Forbes Oriental Memoirs II 514: I lived near four years within a few miles of the solemn groves where those voluptuous devotees pass their lives with the ramjannees, or dancing-girls attached to the temples.
1855		H.H. Wilson Gloss. Judicial & Revenue Terms 437/1: Rámjaní [...] A dancing girl: it is applied also in Bengal, under the corruption of Ramjohnny, to a prostitute.
1886		Yule & Burnell Hobson-Jobson 584/2: Rum-johnny, s. Two distinct meanings are ascribed to this vulgar word, both we believe, obsolete. [...] (b). Among soldiers and sailors, ‘a prostitute’; from Hind. r?mjan?, ‘a dancing-girl.’.
1902		H. Compton Free Lance in a Far Land 93: ‘Why, rot and sink me! but I could tell you some jolly stories about the pretty, skitty, little Ramjohnnies in Indy, with their nose-rings and their toe-rings, and their nicky-nackies, and their coffee skins, and their furbelows, and their faudaugles’.