Immaculate Conception vs creed

Immaculate Conception and creed both are nouns.

Word	Noun	Adjective	Verb	Adverb
Immaculate Conception	Yes	No	No	No
creed	Yes	No	No	No

As nouns, creed is a hypernym of Immaculate Conception; that is, creed is a word with a broader meaning than Immaculate Conception:

Immaculate Conception: (Christianity) the Roman Catholic dogma that God preserved the Virgin Mary from any stain of original sin from the moment she was conceived
creed: the written body of teachings of a religious group that are generally accepted by that group

Other hypernyms of Immaculate Conception include church doctrine, gospel, religious doctrine.

Immaculate Conception (noun)	creed (noun)
(Christianity) the Roman Catholic dogma that God preserved the Virgin Mary from any stain of original sin from the moment she was conceived	any system of principles or beliefs
Roman Catholic holy day first celebrated in 1854	the written body of teachings of a religious group that are generally accepted by that group