Source : Webster's Revised Unabridged Dictionary (1913)

Stuttering \Stut"ter*ing\, a.
   Apt to stutter; hesitating; stammering. -- {Stut"ter*ing*ly},
   adv.

Source : WordNet®

stutteringly
     adv : with a stammer; "`Will you marry me?' he asked stammeringly"
           [syn: {stammeringly}]