dance band vs dance orchestra

dance band and dance orchestra both are nouns.

Word	Noun	Adjective	Verb	Adverb
dance band	Yes	No	No	No
dance orchestra	Yes	No	No	No

As nouns, dance band and dance orchestra are synonyms defined as:

dance band and dance orchestra: a group of musicians playing popular music for dancing

Other synonyms of dance band include band.

dance band (noun)	dance orchestra (noun)
a group of musicians playing popular music for dancing	a group of musicians playing popular music for dancing