Green’s Dictionary of Slang

cow v.2

[cow n.3 ]

1. (US drugs) to put together one’s resources to buy drugs.

Hawes & Asher Raise Up Off Me 45: Make it two dimes and we’ll cow.* [...] *Pool resources to buy dope.

2. (US gambling) to split bets, and thus profits, with a fellow-player.

M. Guberman at CasinoGaming.com 22 July 🌐 How about this one: ‘I see you’ve got a Chicago bankroll there. You seem to be a decent enough player. If you want to move, I’ll go cow with you.’ There’s half a chance he’ll know that a Chicago ’roll is a bunch of dollar bills with a bigger bill folded over them to give the impression one has a lot of money) but will he know what you’re talking about when you want to cow with him? (To go cow with someone means to go half and half with him and splitting profits.).