Green’s Dictionary of Slang

1. to stab.

1885

Bulletin (Sydney) 31 Jan. 7/1: The man who kept the place, however, attempted to close the door on Garo (etc.), when that exasperated individual ventilated the skin of the wine-shop keeper to such an extent, that if he serves his customers at all, he has to serve them from heaven.

2. (orig. US) to shoot, to kill with a bullet; thus ventilation n., shooting.

1873		W.H. Thomes Slaver’s Adventures 99: A few of your countrymen took it into their heads that our hides wanted ventilating.
1907		C.E. Mulford Bar-20 i: ‘Had a argument with C 80 out’n th’ line.’ ‘Go ’way! Ventilate enny?’ ‘One.’.
1916		A. Stringer Door of Dread 85: If any guy tries to stop me from walkin out o’ this house, I’ll ventilate ’em first, and ventilate ’em good.
1934		O. Strange Sudden 58: That there ventilation in my lid weren’t there night before last.
1944		C.S. Montanye ‘Shoulder Straps’ Thrilling Detective Feb. 🌐 Another minute and Hooker would ventilate him with hot lead.
1953		Kramer & Karr Teen-Age Gangs 29: He ain’t been back. So you got to assume that he made contact. Unless he’s been ventilated.
1970		J. Conaway Big Easy 75: Whitey don’t know you got one [...] not till you pull it out and ventilate him.
1979		F. Norman Too Many Crooks Spoil the Caper 161: Grab a cloud you bums or I’ll ventilate you!
1987		(con. 1920s) L. Redmond Emerald Square 43: It was a case of ‘Claw sky, hombre’ or be ventilated.
2020		S.A. Crosby Blacktop Wasteland 208: They day after they had watched him ventilate Quan.