Source : Webster's Revised Unabridged Dictionary (1913)

Indignant \In*dig"nant\, a. [L. indignans, -antis, p. pr. of
   indignari to be indignant, disdain. See {Indign}.]
   Affected with indignation; wrathful; passionate; irate;
   feeling wrath, as when a person is exasperated by unworthy or
   unjust treatment, by a mean action, or by a degrading
   accusation.

         He strides indignant, and with haughty cries To single
         fight the fairy prince defies.           --Tickell.

Source : WordNet®

indignant
     adj : angered at something unjust or wrong; "an indignant denial";
           "incensed at the judges' unfairness"; "a look of
           outraged disbelief"; "umbrageous at the loss of their
           territory" [syn: {incensed}, {outraged}, {umbrageous}]