Green’s Dictionary of Slang

(US) a villain, a rogue, esp. a vagrant who lives on the streets.

1960		H. Selby Jr ‘Tralala’ in Provincetown Rev. 3 81: [She] told them they could stick their fuckin beer up their ass. She didn't need any goddamn skell to buy her a drink.
1973		E. Droge Patrolman 64: A beautiful piece of ass like that screwin’ around with that Black ‘skel’.
1977		E. Torres Q&A 19: See that skell in the dirty sneakers?
1980		W. Sherman Times Square 10: The ‘skells,’ old homeless men and women who carried their belongings in bulging shopping bags […].
1992		R. Price Clockers 422: Even the skells in the cells treated Jimmy like shit.
2001		J. Stahl Plainclothes Naked (2002) 72: His hunch was that Mister Biobrain had been pinched [...] by some skells who thought they were walking off with cash and Rolexes.
2010		Codella and Bennett Alphaville (2011) 5: The skell doesn’t react. He’s chemically unable to.
2017		D. Winslow The Force [ebook] He could be in a situation some skels take his guns and then what’s he supposed to pull, his dick?
2022		J. Hannaham Didn’t Nobody Give a Shit 16: [She] sold little bottles of Thunderbird to the skells of Bed-Stuy.