obi vs cultus

obi and cultus both are nouns.

Word	Noun	Adjective	Verb	Adverb
obi	Yes	No	No	No
cultus	Yes	No	No	No

As nouns, cultus is a hypernym of obi; that is, cultus is a word with a broader meaning than obi:

obi: a religious belief of African origin involving witchcraft and sorcery; practiced in parts of the West Indies and tropical Americas
cultus: a system of religious beliefs and rituals

Other hypernyms of obi include cult, religious cult.

obi (noun)	cultus (noun)
a religious belief of African origin involving witchcraft and sorcery; practiced in parts of the West Indies and tropical Americas	a system of religious beliefs and rituals
(West Indies) followers of a religious system involving witchcraft and sorcery