bay myrtle vs wax myrtle

bay myrtle and wax myrtle both are nouns.

Word	Noun	Adjective	Verb	Adverb
bay myrtle	Yes	No	No	No
wax myrtle	Yes	No	No	No

As nouns, wax myrtle is a hypernym of bay myrtle; that is, wax myrtle is a word with a broader meaning than bay myrtle:

bay myrtle: evergreen aromatic shrubby tree of southeastern United States having small hard berries thickly coated with white wax used for candles
wax myrtle: any shrub or small tree of the genus Myrica with aromatic foliage and small wax-coated berries

bay myrtle (noun)	wax myrtle (noun)
evergreen aromatic shrubby tree of southeastern United States having small hard berries thickly coated with white wax used for candles	any shrub or small tree of the genus Myrica with aromatic foliage and small wax-coated berries