A joke that quite simply isn't funny, or that was once funny but not anymore.
John: What do you call a TV hovering in the dark?
Bill: Here we go again...
John: "DROP IT, NIGGER!" HAHAHA!
Bill: Broke joke, man.
John: What do you mean? That's hilarious!
Bill: You told it six times already this week. That joke went broke. It ran outta funny.
Something a third party says whenever he or she overhears a particularly witty comeback. Similar to owned, or you got served. Like the others, the results are often nonsensical.
Guy 1: Hang on, guys, I just gotta throw this away.
Guy 2: ...I threw yer mom away.
Guy 3: Broke um!