Source : Webster's Revised Unabridged Dictionary (1913)

Dirtily \Dirt"i*ly\, adv.
   In a dirty manner; foully; nastily; filthily; meanly;
   sordidly.

Source : WordNet®

dirtily
     adv 1: in a sordid manner; "as dirtily drunk as usual"
     2: in a filthy unclean manner; "a dirtily dressed camel driver"
        [syn: {filthily}]