Source : Webster's Revised Unabridged Dictionary (1913)

Disrespectful \Dis`re*spect"ful\, a.
   Wanting in respect; manifesting disesteem or lack of respect;
   uncivil; as, disrespectful behavior. --
   {Dis`re*spect"ful*ly}, adv. -- {Dis`re*spect"ful*ness}, n.

Source : WordNet®

disrespectful
     adj 1: exhibiting lack of respect; rude and discourteous; "remarks
            disrespectful of the law"; "disrespectful in the
            presence of his parents"; "disrespectful toward his
            teacher" [ant: {respectful}]
     2: neither feeling nor showing respect [syn: {aweless}, {awless}]