insincere vs false

insincere and false both are adjectives.

Word	Noun	Adjective	Verb	Adverb
insincere	No	Yes	No	No
false	No	Yes	No	Yes

insincere (adjective)	false (adjective)
lacking sincerity	not in accordance with the fact or reality or actuality
	not genuine or real; being an imitation of the genuine article
	adopted in order to deceive
	designed to deceive
	(used especially of persons) not dependable in devotion or affection; unfaithful
	arising from error
	inaccurate in pitch
	deliberately deceptive
	erroneous and usually accidental
	inappropriate to reality or facts

insincere (adverb)	false (adverb)
	in a disloyal and faithless manner