Citrus maxima vs pummelo

Citrus maxima and pummelo both are nouns.

Word	Noun	Adjective	Verb	Adverb
Citrus maxima	Yes	No	No	No
pummelo	Yes	No	No	No

As nouns, Citrus maxima and pummelo are synonyms defined as:

Citrus maxima and pummelo: southeastern Asian tree producing large fruits resembling grapefruits

Other synonyms of Citrus maxima include Citrus decumana, Citrus grandis, pomelo, pomelo tree, shaddock.

Citrus maxima (noun)	pummelo (noun)
southeastern Asian tree producing large fruits resembling grapefruits	southeastern Asian tree producing large fruits resembling grapefruits