Source : Webster's Revised Unabridged Dictionary (1913)

Unkind \Un*kind"\, a.
   1. Not kind; contrary to nature, or the law of kind or
      kindred; unnatural. [Obs.] ``Such unkind abominations.''
      --Chaucer.

   2. Wanting in kindness, sympathy, benevolence, gratitude, or
      the like; cruel; harsh; unjust; ungrateful.

            He is unkind that recompenseth not; but he is most
            unkind that forgetteth.               --Sir T.
                                                  Elyot.
      -- {Un*kind"ly}, adv. -- {Un*kind"ness}, n.

Unkindly \Un*kind"ly\, a.
   1. Not kindly; unkind; ungracious.

   2. Unnatural; contrary to nature. [Obs.] ``Unkindly crime.''
      --Spenser.

   3. Unfavorable; annoying; malignant. --Milton.

Source : WordNet®

unkindly
     adj : lacking in sympathy and kindness; "unkindly ancts" [syn: {unsympathetic}]
     adv : in an unkind manner or with unkindness; "The teacher treats
           the children unkindly" [ant: {kindly}]