credibility vs believability

credibility and believability both are nouns.

Word	Noun	Adjective	Verb	Adverb
credibility	Yes	No	No	No
believability	Yes	No	No	No

As nouns, credibility and believability are synonyms defined as:

credibility and believability: the quality of being believable or trustworthy

Other synonyms of credibility include credibleness.

credibility (noun)	believability (noun)
the quality of being believable or trustworthy	the quality of being believable or trustworthy