bandstand vs outdoor stage

bandstand and outdoor stage both are nouns.

Word	Noun	Adjective	Verb	Adverb
bandstand	Yes	No	No	No
outdoor stage	Yes	No	No	No

As nouns, bandstand and outdoor stage are synonyms defined as:

bandstand and outdoor stage: a platform where a (brass) band can play in the open air

Other synonyms of bandstand include stand.

bandstand (noun)	outdoor stage (noun)
a platform where a (brass) band can play in the open air	a platform where a (brass) band can play in the open air