Green’s Dictionary of Slang

(US black teen) thing; esp. in phr. do your own thang etc.

1965		W. King Jr. ‘The Game’ in Kochman Rappin’ and Stylin’ Out (1972) 394: ‘Your orders, please,’ the waitress said. ‘I’d like to have you, sugar,’ Logan X said. ‘You foxy thang’.
1967		C. Cooper Jr Farm (1968) 5: Speed up! By Gawd, move that Gawd Damn Thang! [Ibid.] 48: That’s the cold thang about you, man.
1971		H.E. Roberts Third Ear n.p.: thang n. a stylish way to pronounce ‘thing’ to indicate identification with Southern blacks.
1978		S. King Stand (1990) 740: I might just pull the trigger on this thang.
1983		G. Tate ‘Cecil Taylor’ in Flyboy in the Buttermilk (1992) 24: Betty Carter [...] once told me that Cecil’s music wasn’t black because whatever thang it was black music was supposed to have, Cecil’s didn’t have one.
1989		P. Munro Sl. U. 189: That girl is such a wild thang.
1991		Dayton Dly News (OH) 29 Sept. 30/2: The ‘thang’ referred to in the title of ’A Powerful Thang’ [...] is sex.
2004		C. Brookmyre Be My Enemy 143: Pretty tits, pretty bum, double penetration and multiple cum shot if that was your thang.