Citrus decumana vs shaddock

Citrus decumana and shaddock both are nouns.

Word	Noun	Adjective	Verb	Adverb
Citrus decumana	Yes	No	No	No
shaddock	Yes	No	No	No

As nouns, Citrus decumana and shaddock are synonyms defined as:

Citrus decumana and shaddock: southeastern Asian tree producing large fruits resembling grapefruits

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

Citrus decumana (noun)	shaddock (noun)
southeastern Asian tree producing large fruits resembling grapefruits	large pear-shaped fruit similar to grapefruit but with coarse dry pulp
	southeastern Asian tree producing large fruits resembling grapefruits