melon vs muskmelon

melon and muskmelon both are nouns.

Word	Noun	Adjective	Verb	Adverb
melon	Yes	No	No	No
muskmelon	Yes	No	No	No

As nouns, muskmelon is a hyponym of melon; that is, muskmelon is a word with a more specific, narrower meaning than melon:

melon: any of numerous fruits of the gourd family having a hard rind and sweet juicy flesh
muskmelon: the fruit of a muskmelon vine; any of several sweet melons related to cucumbers

Other hyponyms of melon include melon ball, sweet melon, watermelon.

As nouns, muskmelon is a hyponym of melon; that is, muskmelon is a word with a more specific, narrower meaning than melon:

melon: any of various fruit of cucurbitaceous vines including: muskmelons, watermelons, cantaloupes, cucumbers
muskmelon: any of several varieties of vine whose fruit has a netted rind and edible flesh and a musky smell

melon (noun)	muskmelon (noun)
any of numerous fruits of the gourd family having a hard rind and sweet juicy flesh	the fruit of a muskmelon vine; any of several sweet melons related to cucumbers
any of various fruit of cucurbitaceous vines including: muskmelons, watermelons, cantaloupes, cucumbers	any of several varieties of vine whose fruit has a netted rind and edible flesh and a musky smell