An exclamation to be shouted loudly at any given moment, usually accompanied by strong feelings. Most of the time, it is associated with anger or frustration. Equivalent to shouting "dammit","darn it","jesus christ", and other such phrases.
Stacy: I'm so glad I studied for that huge history test last night.
John: That's today?! BUTTICUS MAXIMUS!
Mary: Suzie won't stop gossiping about me, and every time I see her, I want to yell, "Butticus maximus! Just shut up already!"
Joan: I know how you feel.