primal vs central

primal is not a noun while central is a noun.

Word	Noun	Adjective	Verb	Adverb
primal	No	Yes	No	No
central	Yes	Yes	No	No

As adjectives, primal and central are synonyms defined as:

Other synonyms of primal include cardinal, fundamental, key.

primal (noun)	central (noun)
	a workplace that serves as a telecommunications facility where lines from telephones can be connected together to permit communication

primal (adjective)	central (adjective)
having existed from the beginning; in an earliest or original stage or state	in or near a center or constituting a center; the inner area
serving as an essential component	serving as an essential component