Green’s Dictionary of Slang

1. to move or treat in a repellent or seedy manner.

1964		Punch 30 Dec. 986/2: Other plays, sleazing across the West End boards.
1988		Jagger & Richard ‘Sad, Sad, Sad’ 🎵 And fools aren’t gonna follow / You don’t need to sleaze about.
2007		R. Milward Apples (2023) 17: I just got stared out by random men [...] Some advice to boys: don’t sleaze us.

2. (US, also schleaze) to acquire in a underhand manner.

1955		E. Hoagland Cat Man 100: Brownie has schleazed the [tiger] cub in some deal only the other day and there wasn’t a cage for it.
1987		(con. 1968) Bunch & Cole Reckoning for Kings (1989) 413: He figured Diaz for a wetback; asshole probably joined the fucking Army so he could sleaze a citizenship.

3. (NZ prison) to bribe.

1999

D. Looser ‘Boob Jargon’ in NZEJ 13 35: sleaze v. To bribe.