Derogatory. It can also be used in noun form to denote any insultive or otherwise negative-sounding word. If you strech this definition slightly, you can have a more concise and mature-sounding version of 'cuss word' or 'four-letter word' while a more specific version of 'curse' or 'swear'. Personally, I use the noun form, while just using 'derogatory' for the adjective. Occasionally, though, I get off my high horse and just say 'bad' or 'mean' like the average plebeian.

Pe*jor"a*tive (?), a. [F. p'ejoratif, fr. L. pejor, used as compar. of malus evil.]

Implying or imputing evil; depreciatory; disparaging; unfavorable.

 

© Webster 1913.