Casava and Mandioc

Casava noun - Any of several plants of the genus Manihot having fleshy roots yielding a nutritious starch.

Mandioc and casava are semantically related. In some cases you can replace term "Mandioc" with "Casava", this nouns are similar.

Mandioc noun - Cassava with long tuberous edible roots and soft brittle stems; used especially to make cassiri (an intoxicating drink) and tapioca.

Casava and mandioc are semantically related. You can use "Casava" instead a noun "Mandioc".