To piss away: to waste or squander time, money, etc.
He piddled away three hours at the bus station waiting for Gabe to show up.
To fail to do one's work; to goof off.
To leave; to bugger off.
To remove the lid of a jar or other container by unscrewing it.
To tell someone to leave or to stop being bothersome.
An expression of surprise or disbelief.