affirmative vs approbatory

affirmative is a noun but approbatory is not a noun.

Word	Noun	Adjective	Verb	Adverb
affirmative	Yes	Yes	No	No
approbatory	No	Yes	No	No

As adjectives, affirmative and approbatory are synonyms defined as:

affirmative and approbatory: expressing or manifesting praise or approval

Other synonyms of affirmative include approbative, approving, plausive.

affirmative (noun)	approbatory (noun)
a reply of affirmation

affirmative (adjective)	approbatory (adjective)
affirming or giving assent	expressing or manifesting praise or approval
expressing or manifesting praise or approval
expecting the best