Source : Webster's Revised Unabridged Dictionary (1913)

Respectful \Re*spect"ful\ (-f?l), a.
   Marked or characterized by respect; as, respectful
   deportment.

         With humble joi and with respectful fear. --Prior.
   -- {Re*spect"ful*ly}, adv. -- {Re*spect"ful*ness}, n.

Source : WordNet®

respectfully
     adv : in a respectful manner; "might I respectfully suggest to the
           Town Council that they should adopt a policy of
           masterly inactivity?" [syn: {with all respect}] [ant: {disrespectfully}]