plausive vs approving

plausive is not a noun while approving is a noun.

Word	Noun	Adjective	Verb	Adverb
plausive	No	Yes	No	No
approving	Yes	Yes	No	No

As adjectives, plausive and approving are synonyms defined as:

Other synonyms of plausive include affirmative, approbative, approbatory.

plausive (noun)	approving (noun)
	the formal act of approving

plausive (adjective)	approving (adjective)
expressing or manifesting praise or approval	expressing or manifesting praise or approval