Source : Webster's Revised Unabridged Dictionary (1913)

Slimly \Slim"ly\, adv.
   In a state of slimness; in a slim manner; slenderly.

Source : WordNet®

slimly
     adv : in a slim or slender manner; "a slenderly built woman";
           "slightly built" [syn: {slenderly}, {slightly}]