acid vs acidulate

acid is a noun but acidulate is not a noun.

Word	Noun	Adjective	Verb	Adverb
acid	Yes	Yes	No	No
acidulate	No	No	Yes	No

acid (noun)	acidulate (noun)
street name for lysergic acid diethylamide
any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt

acid (adjective)	acidulate (adjective)
having the characteristics of an acid
being sour to the taste
harsh or corrosive in tone

acid (verb)	acidulate (verb)
	make sour or more sour