'round-leaf' is a modern English compound formed from 'round' + 'leaf'. 'round' comes into English via Old French 'rond' (from Latin 'rotundus'), and 'leaf' comes from Old English 'lēaf'.

'round' entered Middle English from Old French 'rond' (ultimately from Latin 'rotundus'), while 'leaf' derives from Old English 'lēaf'; the compound arose by combining the adjective + noun in later Middle to Modern English to describe leaf shape.

Initially it denoted literally 'a leaf that is round' or 'having round leaves'; this literal descriptive meaning has been retained in modern usage.