 The common name "spurge" derives from the Middle English/Old French "espurge" ("to purge"), due to the use of the plant's sap as a purgative.The botanical name "Euphorbia" derives from Euphorbos, the Greek physician of King Juba II of Numidia (52–50 BC – 23 AD), who married the daughter of Anthony and Cleopatra.Juba was a prolific writer on various subjects, including natural history.