stereo system vs stereophonic system

stereo system and stereophonic system both are nouns.

Word	Noun	Adjective	Verb	Adverb
stereo system	Yes	No	No	No
stereophonic system	Yes	No	No	No

As nouns, stereo system and stereophonic system are synonyms defined as:

stereo system and stereophonic system: reproducer in which two microphones feed two or more loudspeakers to give a three-dimensional effect to the sound

Other synonyms of stereo system include stereo, stereophony.

stereo system (noun)	stereophonic system (noun)
reproducer in which two microphones feed two or more loudspeakers to give a three-dimensional effect to the sound	reproducer in which two microphones feed two or more loudspeakers to give a three-dimensional effect to the sound