undependable vs uncertain

undependable and uncertain both are adjectives.

Word	Noun	Adjective	Verb	Adverb
undependable	No	Yes	No	No
uncertain	No	Yes	No	No

undependable (adjective)	uncertain (adjective)
not worthy of reliance or trust	not established beyond doubt; still undecided or unknown
liable to be erroneous or misleading	lacking or indicating lack of confidence or assurance
	not certain to occur; not inevitable
	not established or confirmed
	ambiguous (especially in the negative)
	not consistent or dependable
	subject to change