Someone who uses a lot of profanity and isn't even aware how offensive he/she is being.
V-Bo is always talking about how men clean their genitals and she sure likes to say the words 'bitch.' She is a foul mouth!
by ponyup May 19, 2009
Used to describe someone who uses a lot of inappropriate or vulgar langauge when speaking, mainly swear words or dirty words.
Hey! Foulmouth! Come here!
by geezywheezy665 March 08, 2009