registration vs credentials

registration and credentials both are nouns.

Word	Noun	Adjective	Verb	Adverb
registration	Yes	No	No	No
credentials	Yes	No	No	No

As nouns, credentials is a hypernym of registration; that is, credentials is a word with a broader meaning than registration:

Other hypernyms of registration include certificate, certification, credential.

registration (noun)	credentials (noun)
the act of enrolling	a document attesting to the truth of certain stated facts
the act of adjusting something to match a standard
(music) the sound property resulting from a combination of organ stops used to perform a particular piece of music; the technique of selecting and adjusting organ stops
a document certifying an act of registering
the body of people (such as students) who register or enroll at the same time