look up any word, like ratchet:
this word is an extremly bad insult or used correctly a really good complement.

its pronounced bas-toy-es
Alex: that party last night was awesome!!
Phoenix: yeah, it was proper fuckin' bastoise

Phoenix: Alex your a dickhead for stealin one of ma superkings boi.
Alex: ye fack off mace you fackin bastoise
by ehhhhh dickhead March 07, 2010
6 1