Source : Webster's Revised Unabridged Dictionary (1913)

Vulgar \Vul"gar\, a. [L. vulgaris, from vulgus the multitude,
   the common people; of uncertain origin: cf. F. vulgaire. Cf.
   {Divulge}.]
   1. Of or pertaining to the mass, or multitude, of people;
      common; general; ordinary; public; hence, in general use;
      vernacular. ``As common as any the most vulgar thing to
      sense. '' -- Shak.

            Things vulgar, and well-weighed, scarce worth the
            praise.                               --Milton.

            It might be more useful to the English reader . . .
            to write in our vulgar language.      --Bp. Fell.

            The mechanical process of multiplying books had
            brought the New Testament in the vulgar tongue
            within the reach of every class.      --Bancroft.

   2. Belonging or relating to the common people, as
      distinguished from the cultivated or educated; pertaining
      to common life; plebeian; not select or distinguished;
      hence, sometimes, of little or no value. ``Like the vulgar
      sort of market men.'' --Shak.

            Men who have passed all their time in low and vulgar
            life.                                 --Addison.

            In reading an account of a battle, we follow the
            hero with our whole attention, but seldom reflect on
            the vulgar heaps of slaughter.        --Rambler.

   3. Hence, lacking cultivation or refinement; rustic; boorish;
      also, offensive to good taste or refined feelings; low;
      coarse; mean; base; as, vulgar men, minds, language, or
      manners.

            Be thou familiar, but by no means vulgar. --Shak.

   {Vulgar fraction}. (Arith.) See under {Fraction}.

Vulgar \Vul"gar\, n. [Cf. F. vulgaire.]
   1. One of the common people; a vulgar person. [Obs.]

            These vile vulgars are extremely proud. --Chapman.

   2. The vernacular, or common language. [Obs.]

Source : WordNet®

vulgar
     adj 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" [syn: {coarse}, {common},
             {rough-cut}, {uncouth}]
     2: 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"
        [syn: {common}, {plebeian}, {unwashed}]
     3: 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"
        [syn: {common}, {vernacular}]
     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" [syn: {coarse}, {crude}, {earthy}, {gross}]