diffuser vs baffle board

diffuser and baffle board both are nouns.

Word	Noun	Adjective	Verb	Adverb
diffuser	Yes	No	No	No
baffle board	Yes	No	No	No

As nouns, baffle board is a hypernym of diffuser; that is, baffle board is a word with a broader meaning than diffuser:

diffuser: baffle that distributes sound waves evenly
baffle board: a flat plate that controls or directs the flow of fluid or energy

Other hypernyms of diffuser include baffle.

diffuser (noun)	baffle board (noun)
optical device that distributes the light of a lamp evenly	a flat plate that controls or directs the flow of fluid or energy
baffle that distributes sound waves evenly