Cassava. Manioc. Yuca. Fleshy, starchy tubers with tough brown skin and crisp white flesh, originally from Brazil but now widely cultivated. There are two types, sweet and bitter. Avoid the bitter one. Throughout the Amazon basin there are 26 varieties, each thriving under different conditions. The process of making it into flour or tapioca removes the toxins. You may see the singular partitive form "kassavaa".