Modern coinage, a blend of Rhoda and Rhona. It is now often taken to be a Welsh name derived from rhon ‘pike, lance’ (as in Rhonwen;) + -da ‘good’, as in Glenda. The name is associated particularly with the American film actress Rhonda Fleming (b. 1923 as Marilyn Louis).
English: from Anglo-Norman French gerner ‘granary’ (Old French grenier, from Late Latin granarium, a derivative of granum ‘grain’). It may have been a topographic name for someone who lived near a barn or granary, or a metonymic occupational name for someone in charge of the stores kept in a granary.