Source : Webster's Revised Unabridged Dictionary (1913)

Fashionably \Fash"ion*a*bly\, adv.
   In a fashionable manner.

Source : WordNet®

fashionably
     adv : in a fashionable manner; "his voice had no trace of the
           drawl that you would expect to find in a fashionably
           dressed young man" [ant: {unfashionably}]