A quantity of marijuana worth £5 i.e halh a tens, a quarter of an eighth.
I've only got enough to pick up a jacks.
alone; single; partnerless; not in a group;
i'm on my jacks.
or
i'm on my j's (abbrev)
Set of nice titties. A pair of boobs.
Whoah, that broad had a set of jacks on her!
Irish term for the toilet
just off to the jacks for a number two