bitter cassava vs casava

bitter cassava and casava both are nouns.

Word	Noun	Adjective	Verb	Adverb
bitter cassava	Yes	No	No	No
casava	Yes	No	No	No

As nouns, casava is a hypernym of bitter cassava; that is, casava is a word with a broader meaning than bitter cassava:

bitter cassava: cassava with long tuberous edible roots and soft brittle stems; used especially to make cassiri (an intoxicating drink) and tapioca
casava: any of several plants of the genus Manihot having fleshy roots yielding a nutritious starch

Other hypernyms of bitter cassava include cassava.

bitter cassava (noun)	casava (noun)
cassava with long tuberous edible roots and soft brittle stems; used especially to make cassiri (an intoxicating drink) and tapioca	any of several plants of the genus Manihot having fleshy roots yielding a nutritious starch