Source : Webster's Revised Unabridged Dictionary (1913)

Benignant \Be*nig"nant\, a. [LL. benignans, p. pr. of benignare,
   from L. benignus. See {Benign}.]
   Kind; gracious; favorable. -- {Be*nig"nant*ly}, adv.

Source : WordNet®

benignantly
     adv : in a benign manner; "this drug is benignly soporific" [syn:
           {benignly}]