Source : Webster's Revised Unabridged Dictionary (1913)

Dishonorable \Dis*hon"or*a*ble\, a. [Cf. F. d['e]shonorable.]
   1. Wanting in honor; not honorable; bringing or deserving
      dishonor; staining the character, and lessening the
      reputation; shameful; disgraceful; base.

   2. Wanting in honor or esteem; disesteemed.

            He that is dishonorable in riches, how much more in
            poverty!                              --Ecclus. x.
                                                  31.

            To find ourselves dishonorable graves. --Shak.
      -- {Dis*hon"or*a*ble*ness}, n. -- {Dis*hon"or*a*bly}, adv.

Source : WordNet®

dishonorable
     adj 1: lacking honor or integrity; deserving dishonor;
            "dishonorable in thought and deed"; "a dishonorable
            discharge" [syn: {dishonourable}] [ant: {honorable}]
     2: deceptive or fraudulent; disposed to cheat or defraud or
        deceive [syn: {dishonest}] [ant: {honest}]
     3: not bringing honor and glory; "some mute inglorious Milton
        here may rest" [syn: {inglorious}] [ant: {glorious}]
     4: not adhering to ethical or moral principles; "base and
        unpatriotic motives"; "a base, degrading way of life";
        "cheating is dishonorable"; "they considered colonialism
        immoral"; "unethical practices in handling public funds"
        [syn: {base}, {dishonourable}, {immoral}, {unethical}]
     5: morally unacceptable; "the dishonorable conduct of trusted
        men" [syn: {dishonourable}]