The leading piece of a turd which protrudes from the anus often causing the skid mark. Can also be used to describe a person who may otherwise be referred to as a douchebag.

v. collectively or individually finding someone/something to blame for a problem, as opposed to brainstorming which connotes finding solutions to a problem

n. the act of finding someone/something to blame for a problem

(from a TV ad for HD television)