vulgar in WordNet English dictionary

1. lacking refinement or cultivation or taste
   "he had coarse manners but a first-rate mind"; "behavior that branded him as common"; "an untutored and uncouth human being"; "an uncouth soldier--a real tough guy"; "appealing to the vulgar taste for violence"; "the vulgar display of the newly rich"
   coarse  common  rough-cut  uncouth  vulgar 
   
2. being or characteristic of or appropriate to everyday language
   "common parlance"; "a vernacular term"; "vernacular speakers"; "the vulgar tongue of the masses"; "the technical and vulgar names for an animal species"
   common  vernacular  vulgar 
   
3. of or associated with the great masses of people
   "the common people in those days suffered greatly"; "behavior that branded him as common"; "his square plebeian nose"; "a vulgar and objectionable person"; "the unwashed masses"
   common  plebeian  vulgar  unwashed 
   
4. conspicuously and tastelessly indecent
   "coarse language"; "a crude joke"; "crude behavior"; "an earthy sense of humor"; "a revoltingly gross expletive"; "a vulgar gesture"; "full of language so vulgar it should have been edited"
   crude  earthy  gross  vulgar