Having a Party. Usually with beer and/or weed.
Are we throwing down at your house tonight?
Yea bring the booze.
To contribute money towards the purchase of something.
JohnO: hey, Homs I'm gunna go get some monsters, You want some?
Homs: Yea man, I'll throw down.
To contribute money to marijuana.
I'll throw down $5 for that sack
some boys were all up in our ish so we hadta throw down ta represent.
(a) it's halloween bro. i want to party, let's throw down!
(b) that epic douche kept txting my girlfriend, so we had to throw down.
(c) she was only like 100lbs, but we had some beers last night and she could really throw down!