Green’s Dictionary of Slang

flashy, vulgar, whether in speech or appearance.

1822		Lit. Gaz. 13 Apr. 223/2: It is, to speak in the writer’s fashion, sloppy and slangy.
1832		R. Chambers Bk of Days II 274/2: The delighted monarch ordered the filthy, slangy, low play, to be performed three several times in his kingly presence.
1843		R.S. Surtees Handley Cross (1854) 143: All the idle, dog-stealing raffs in the country — flash, slangey-looking scamps.
1843		R.S. Surtees Handley Cross (1854) 380: ‘I say, guv’nor!’ exclaimed he, in the slangy, saucy, dialect, peculiar to the lower orders in London.
1853		R.S. Surtees Mr Sponge’s Sporting Tour 9: Dirty-shirted, sloggering, baggy-breeched, slangey-gaitered fellows.
1865		Dickens Our Mutual Friend (1994) 261: Both were too gaudy, too slangy, too odorous of cigars, and too much given to horseflesh.
1872		H. Smart False Cards I 4: [T]hrowing off the coat which had been the subject of his late laudation, and slipping into a more slangy garment.
1874		H. Mayhew London Characters 44: A mild but slangy youth of two-and-twenty.
1877		Chicago Trib. 7 Apr. 3/1: Our language is ‘prime’ / [...] / Never mind what they say / About its being slangy and ‘snide’.
1884		Randiana 45: Dear me, how damnation slangy I am getting to-night.
1887		‘A Plain Woman’ Poor Nellie I 31: Looked awfully slangy, then.
1894		G. du Maurier Trilby 126: She was no longer slangy in French.
1899		Ade Fables in Sl. (1902) 185: Myrtle [...] had been schooled in the Proprieties, and it was not to be supposed that she would crave the Society of slangy old Gus.
1901		W. Irwin ‘An Inside Con to Refined Guys’ in Love Sonnets of a Hoodlum 13: The French Villon, Before Jack Hangman yanked him high, Quilled slangy guff and Frenchy stuff.
1914		Sun. Times (Perth) 13 Dec. 8/8: His Honor’s no larrikin slangy / His tongue isn’t turfy or twangy.
1918		C. Sandburg letter 12 Sept. in Mitgang (1968) 137: He is too slangy, abrupt [...] and human to be able to function properly on the News.
1925		S. Lewis Arrowsmith 63: A thin and slangy young woman apparently from the West.
1946		(con. 1912) B. Marshall George Brown’s Schooldays 88: ‘All right, keep your hair on,’ Abinger said. ‘I say, we are getting slangy, aren’t we?’ Brown said.
1953		W. Fisher Waiters 191: ‘We’re gonna have a ball,’ Dowd would say, [...] as he emulated an adolescent’s slangy language.