When you snatch something, you grab it — either literally or figuratively. You might eagerly snatch the TV remote or your best friend's idea. Snatching can be nasty.
You might snatch a lost balloon before it gets away, or snatch your cat before he can escape the room. The verb snatch can also be used in a figurative way, like when you snatch the first job offer that comes your way after graduating from college. The origin is most likely the Middle English word snacche, which means "to suddenly snap at," or in its noun form, "a trap."