art class vs class

art class and class both are nouns.

Word	Noun	Adjective	Verb	Adverb
art class	Yes	No	No	No
class	Yes	No	Yes	No

As nouns, class is a hypernym of art class; that is, class is a word with a broader meaning than art class:

Other hypernyms of art class include course, course of instruction, course of study.

art class (noun)	class (noun)
a class in which you learn to draw or paint	education imparted in a series of lessons or meetings
	elegance in dress or behavior
	a collection of things sharing a common attribute
	people having the same social, economic, or educational status
	(biology) a taxonomic group containing one or more orders
	a body of students who are taught together
	a body of students who graduate together
	a league ranked by quality

art class (verb)	class (verb)
	arrange or order by classes or categories