tannoy vs speaker unit

tannoy and speaker unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
tannoy	Yes	No	No	No
speaker unit	Yes	No	No	No

As nouns, speaker unit is a hypernym of tannoy; that is, speaker unit is a word with a broader meaning than tannoy:

tannoy: a loudspeaker
speaker unit: electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance

Other hypernyms of tannoy include loudspeaker, loudspeaker system, speaker, speaker system.

tannoy (noun)	speaker unit (noun)
a loudspeaker	electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance