water vine
/ˈwɔːtə vʌɪn/noun
Any of various tropical climbing plants whose stems contain a copious and potentially drinkable watery sap, including some true vines (genus Vitis) and members of the genera Tetracera (family Dilleniaceae: West Africa), Doliocarpus (family Dilleniaceae: tropical America), Phytocrene (family Icacinaceae: south-east Asia), and Cissus (family Vitaceae: Australasia).
Origin
Late 18th century; earliest use found in Edward Long (1734–1813), planter and commentator on Jamaican affairs. From water + vine.