Why So Serious?

Me : What do you call a boomerang that doesn't come back when you throw it?
Friend : A malfunction boomerang?
Me : It's a stick
Friend : A stick which comes back when you throw it is called boomerang, not a boomerang that doesn't come when you throw it is called a stick
Me : Errr... *I was trying to tell a joke, why so serious?*