to a faint degree or weakly perceived; "between him and
the dim light a form was outlined faintly"; "stars shining faintly through the overcast"; "could hear his distant shouts only faintly"; "the rumors weren't even faintly true"
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Faintly \Faint"ly\, adv.
In a faint, weak, or timidmanner.