'Truthfully' definitions:

Definition of 'truthfully'

From: WordNet
adverb
With truth; "I told him truthfully that I had just returned from my vacation"; "he answered the question as truthfully as he could" [ant: mendaciously, untruthfully]

Definition of 'Truthfully'

From: GCIDE
  • Truthful \Truth"ful\, a. Full of truth; veracious; reliable. -- {Truth"ful*ly}, adv. -- {Truth"ful*ness}, n. [1913 Webster]