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®

dishonorably
     adv 1: in a dishonorable manner; "he acted dishonorably" [ant: {honorably}]
     2: with dishonor; "he was dishonorably discharged" [ant: {honorably}]
     3: in a dishonorably manner or to a dishonorable degree; "his
        grades were disgracefully low" [syn: {disgracefully}, {ingloriously},
         {ignominiously}, {discreditably}, {shamefully}, {dishonourably}]