expo vs art exhibition

expo and art exhibition both are nouns.

Word	Noun	Adjective	Verb	Adverb
expo	Yes	No	No	No
art exhibition	Yes	No	No	No

As nouns, art exhibition is a hyponym of expo; that is, art exhibition is a word with a more specific, narrower meaning than expo:

expo: a collection of things (goods or works of art etc.) for public display
art exhibition: an exhibition of art objects (paintings or statues)

Other hyponyms of expo include peepshow, raree-show, fair.

expo (noun)	art exhibition (noun)
a collection of things (goods or works of art etc.) for public display	an exhibition of art objects (paintings or statues)