papaya vs melon tree

papaya and melon tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
papaya	Yes	No	No	No
melon tree	Yes	No	No	No

As nouns, papaya and melon tree are synonyms defined as:

papaya and melon tree: tropical American shrub or small tree having huge deeply palmately cleft leaves and large oblong yellow fruit

Other synonyms of papaya include Carica papaya, papaia, papaya tree, pawpaw.

papaya (noun)	melon tree (noun)
large oval melon-like tropical fruit with yellowish flesh	tropical American shrub or small tree having huge deeply palmately cleft leaves and large oblong yellow fruit
tropical American shrub or small tree having huge deeply palmately cleft leaves and large oblong yellow fruit