symphony vs symphony orchestra

symphony and symphony orchestra both are nouns.

Word	Noun	Adjective	Verb	Adverb
symphony	Yes	No	No	No
symphony orchestra	Yes	No	No	No

As nouns, symphony and symphony orchestra are synonyms defined as:

symphony and symphony orchestra: a large orchestra; can perform symphonies

Other synonyms of symphony include philharmonic.

symphony (noun)	symphony orchestra (noun)
a long and complex sonata for symphony orchestra	a large orchestra; can perform symphonies
a large orchestra; can perform symphonies