When you're fingering a girl and you "accidentally" put a finger in her butthole

Stacy: wtf?!
Dan: sorry I guess I'm a little clumsy thumbsy tonight

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)