Credibility :: Credibility (n.) The quality of being credible; credibleness; as, the credibility of facts; the credibility of witnesses..
Credible :: Credible (a.) Capable of being credited or believed; worthy of belief; entitled to confidence; trustworthy.
Credibleness :: Credibleness (n.) The quality or state of being credible; worthiness of belief; credibility.
Credibly :: Credibly (adv.) In a manner inducing belief; as, I have been credibly informed of the event..
Incredibility :: Incredibility (n.) The quality or state of being incredible; incredibleness.
Incredible :: Incredible (a.) Not credible; surpassing belief; too extraordinary and improbable to admit of belief; unlikely; marvelous; fabulous.