treacherously vs treacherous

treacherously is not an adjective while treacherous is an adjective.

Word	Noun	Adjective	Verb	Adverb
treacherously	No	No	No	Yes
treacherous	No	Yes	No	No

treacherously (adjective)	treacherous (adjective)
	dangerously unstable and unpredictable
	tending to betray; especially having a treacherous character as attributed to the Carthaginians by the Romans

treacherously (adverb)	treacherous (adverb)
in a disloyal and faithless manner