Being foulmouthed is often seen as inappropriate behavior in many situations. However, if you need to describe someone who is using profanity in an alternative way, there are several synonyms that you may consider. Some of them may describe the behavior as being vulgar, obscene, or crass. Other words that capture the essence of foul language include defamatory, abusive, or foul-tongued. Alternatively, phrases like profanity-laden, expletive-filled, or vituperative speech could also be used to convey the same meaning. Whatever word or phrase you choose, it is important to maintain a level of professionalism when communicating with others and avoid any offensive language.