fearfully

from WordNet (r) 3.0 (2006)

fearfully
    adv 1: in fear, "she hurried down the stairs fearfully" [ant:
           {dauntlessly}, {fearlessly}, {intrepidly}]
    2: in an alarming manner; "they were fearfully attacked"

from The Collaborative International Dictionary of English v.0.48

Fearfully \Fear"ful*ly\, adv.
   In a fearful manner.
   [1913 Webster]