potty-mouthed 
adjective informal
Using or characterized by bad language: a potty-mouthed rapper...
- Their daughter is an insecure, arrogant, butt-ugly, obnoxious, potty-mouthed, uneducated, fat liberal who makes fun of God and Christians all the time.
- But this does not diminish the fact that living with a Very Boy-like Boy has added a whole assortment of new potty-mouthed phrases to my obviously deprived vocabulary.
- Not because I am prudish about the use of cuss words (I am, after all, in the Marines and work around potty-mouthed sailors all day).
Derivatives
potty mouth
- And give them full points for managing to come across like total potty-mouths without ever saying a real-live nasty word.
- Depressed that your potty-mouth is banished from the letters page?
- ‘I used to think my kids got their potty-mouths from the stuff they saw on TV and radio,’ testified one frustrated parent.