Someone who says one thing and does another. A typical example is when a girl leads
guy with flattery and false promises of
something developing. After weeks of talking and the
guy suggesting a meet u, the girl usually starts stalling or finds any excuses because she didn't have any intention of meeting the first place. This is what a joker is and their jokes are usually at your expense and having your time wasted.
Greg: So did you meet that girl, what's her name again; Lynn over the weekend
Adam: Nooo man! turns out she's a joker
Greg: Oh sorry
bud maybe better
luck next time