imagism vs art movement

imagism and art movement both are nouns.

Word	Noun	Adjective	Verb	Adverb
imagism	Yes	No	No	No
art movement	Yes	No	No	No

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

imagism: a movement by American and English poets early in the 20th century in reaction to Victorian sentimentality; used common speech in free verse with clear concrete imagery
art movement: a group of artists who agree on general principles

Other hypernyms of imagism include artistic movement.

imagism (noun)	art movement (noun)
a movement by American and English poets early in the 20th century in reaction to Victorian sentimentality; used common speech in free verse with clear concrete imagery	a group of artists who agree on general principles