Someone who either sucks at a particular activity, completely sucks at everything, or just sucks at life in general. Such as if your playing football and someone can't ever catch the ball, or if your out skating and someone can't do an incredibly easy trick: they are a sucky-pants. Because they suck.
Timmy can't even kickflip! What a horrible little sucky-pants.
by Stuy Lewis October 11, 2005