Green’s Dictionary of Slang

1. of animate and inanimate objects, too old or worn-out to be of use; thus of a man, impotent.

1700		N. Ward Step to Stir-Bitch Fair in Writings II 251: He was grown Old and past it.
1866		J. Greenwood Little Ragamuffin 233: Spider don’t work at all – he’s past it.
1937		R. Westerby Wide Boys Never Work (1938) 199: In back rooms off Lisle Street ageing tarts who are past it wish the hell they could just go to bed alone.
1943		‘Henry Green’ Caught (2001) 109: Not to mention myself, men like old Piper, who are utterly past it.
1959		F. Norman Fings I i: Lil has been on the game for over ten years, but, like Fred, she is now past it.
1966		T. Keyes All Night Stand 113: I’ve been with Rocco a couple of times, but if you ask me he’s past it.
1970		G.F. Newman Sir, You Bastard 141: Perhaps I’m getting past it.
1978		F. Norman Dead Butler Caper 31: He’d gone to gut, but he wasn’t past it.
1985		J. Sullivan ‘To Hull and Back’ Only Fools and Horses [TV script] Maybe I’m past it Hoskins, my hunches don’t seem to pay off anymore.
1999		Observer 29 Aug. 27: Of course, it could be that I’m past it [...] wistful for a bygone era.
2000		N. Griffiths Grits 75: Ow old’s Reed now, fifty? Over fifty? Fuckin past it anyway.
2001		Guardian G2 8 May 11: At 42, is Barbie past it?

2. dead.

1963–74		B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 98: Try and [...] meet a few sheilahs who aren’t flamin’ past it.
1990		(con. early 1950s) J. Ellroy L.A. Confidential 440: No artful desecrations – his man was past it now.