'Harmfully' definitions:

Definition of 'harmfully'

From: WordNet
adverb
In a detrimental manner [syn: detrimentally, harmfully, noxiously] [ant: harmlessly]

Definition of 'Harmfully'

From: GCIDE
  • Harmful \Harm"ful\ (h[aum]rm"f[.u]l), a. Full of harm; injurious; hurtful; mischievous. " Most harmful hazards." --Strype. --{Harm"ful*ly}, adv. -- {Harm"ful*ness}, n. [1913 Webster]

Synonyms of 'harmfully'

From: Moby Thesaurus