superman vs acid

superman and acid both are nouns.

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

As nouns, superman and acid are synonyms defined as:

superman (noun)	acid (noun)
street name for lysergic acid diethylamide	street name for lysergic acid diethylamide
a person with great powers and abilities	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

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