Phrase meant to lure an unexpecting companion into saying the phrase "What?". If this phrase is responded to with "What?", then that person is presumed to be an "ass-sphinkter" or ass-hole.
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!