boom box vs stereo

boom box and stereo both are nouns.

Word	Noun	Adjective	Verb	Adverb
boom box	Yes	No	No	No
stereo	Yes	Yes	No	No

As nouns, stereo is a hypernym of boom box; that is, stereo is a word with a broader meaning than boom box:

boom box: a portable stereo
stereo: reproducer in which two microphones feed two or more loudspeakers to give a three-dimensional effect to the sound

Other hypernyms of boom box include stereo system, stereophonic system, stereophony.

boom box (noun)	stereo (noun)
a portable stereo	reproducer in which two microphones feed two or more loudspeakers to give a three-dimensional effect to the sound
	two photographs taken from slightly different angles that appear three-dimensional when viewed together

boom box (adjective)	stereo (adjective)
	designating the reproduction of sound using two or more independent audio channels