tapioca plant ta·pio·cap·lant uncommon noun 1. cassava with long tuberous edible roots and soft brittle stems; used especially to make cassiri (an intoxicating drink) and tapioca Synonymsbitter cassavamaniocmandiocmandiocatapioca plantgariManihot esculentaManihot utilissima Related words Broader terms cassava Part of cassavacassiri WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.