secular vs mundane

secular is a noun but mundane is not a noun.

Word	Noun	Adjective	Verb	Adverb
secular	Yes	Yes	No	No
mundane	No	Yes	No	No

secular (noun)	mundane (noun)
someone who is not a clergyman or a professional person

secular (adjective)	mundane (adjective)
of or relating to clergy not bound by monastic vows	belonging to this earth or world; not ideal or heavenly
not concerned with or devoted to religion	found in the ordinary course of events
characteristic of or devoted to the temporal world as opposed to the spiritual world	concerned with the world or worldly matters
of or relating to the doctrine that rejects religion and religious considerations
characteristic of those who are not members of the clergy