whispering gallery vs dome

whispering gallery and dome both are nouns.

Word	Noun	Adjective	Verb	Adverb
whispering gallery	Yes	No	No	No
dome	Yes	No	No	No

As nouns, dome is a hypernym of whispering gallery; that is, dome is a word with a broader meaning than whispering gallery:

whispering gallery: a space beneath a dome or arch in which sounds produced at certain points are clearly audible at certain distant points
dome: a hemispherical roof

whispering gallery (noun)	dome (noun)
a space beneath a dome or arch in which sounds produced at certain points are clearly audible at certain distant points	a hemispherical roof
	a stadium that has a roof
	informal terms for a human head
	a concave shape whose distinguishing characteristic is that the concavity faces downward