1. A compound word containing the words "ass" and "dick." When put together, it means to be the ultamite form of an idiot, jerk off, or jack ass.
2. It can also be used as an expression of excitement.
3. More commonly, it is randomly screamed out to make people look.
2. "Assdick!" I yelled as the kid knocked my glass over.
3. ASSDICK! Wait what?
The purpose of the assdick is to block the entrace of unwanted objects (such as other penises) into the anal cavity. When the assdick senses an incoming threat, it immediately erects to disallow entry.
Tyrone: YOU'RE AN ASS DICK!
Bobby: Say what? I haven't got a dick stuck up my ass!
Tyrone: You're gay, and Thai! GET OUT HERE YOU MINORITY!
adjective - a person who is enough of a jerk to be called an ass and a dick at once i.e. one who is a rude/mean and a tool at once and possibly all of the time.