Source : Webster's Revised Unabridged Dictionary (1913)

Signally \Sig"nal*ly\, adv.
   In a signal manner; eminently.

Source : WordNet®

signally
     adv 1: as a signal; "a term that is used signally rather than
            symbolically"
     2: in a signal manner; "signally inappropriate methods" [syn: {unmistakably},
         {remarkably}]