casaba vs winter melon

casaba and winter melon both are nouns.

Word	Noun	Adjective	Verb	Adverb
casaba	Yes	No	No	No
winter melon	Yes	No	No	No

As nouns, winter melon is a hypernym of casaba; that is, winter melon is a word with a broader meaning than casaba:

casaba: melon having yellowish rind and whitish flesh
winter melon: the fruit of the winter melon vine; a green melon with pale green to orange flesh that keeps well

casaba (noun)	winter melon (noun)
melon having yellowish rind and whitish flesh	the fruit of the winter melon vine; a green melon with pale green to orange flesh that keeps well
	any of a variety of muskmelon vines having fruit with a smooth white rind and white or greenish flesh that does not have a musky smell