multimedia vs multimedia system

multimedia and multimedia system both are nouns.

Word	Noun	Adjective	Verb	Adverb
multimedia	Yes	No	No	No
multimedia system	Yes	No	No	No

As nouns, multimedia and multimedia system are synonyms defined as:

multimedia and multimedia system: transmission that combine media of communication (text and graphics and sound etc.)

multimedia (noun)	multimedia system (noun)
transmission that combine media of communication (text and graphics and sound etc.)	transmission that combine media of communication (text and graphics and sound etc.)