Green’s Dictionary of Slang

to threaten, to menace.

1968		J. Barlow Burden of Proof 134: You can’t tell these days. People are being heavied.
1985		P. Corris ‘Rhythm Track’ in Big Drop 164: ‘I don’t want to heavy you but this needs straightening out’.
1989		Hackworth & Sherman About Face (1991) 200: The sergeant started to heavy me, but then my boys stood up.
1997		P. Corris Washington Club [ebook] ‘[T]ell me about this bloke who heavied you’.
2003		P. Corris Master’s Mates 158: ‘If you heavy him he’s likely to turn into just another cowboy nuisance like me’.