Source : Webster's Revised Unabridged Dictionary (1913)

Unreserved \Un`re*served"\, a.
   Not reserved; not kept back; not withheld in part;
   unrestrained. -- {Un`re*serv"ed*ly}, adv. --
   {Un`re*serv"ed*ness}, n.

Source : WordNet®

unreservedly
     adv : without reservation; "I can unreservedly recommend this
           restaurant!"