rocket [M16th] Rocket comes ultimately from Italian rocca ‘a distaff’, the stick or spindle on which wool was wound for spinning. Like the firework, it was cylindrical in shape. The development of rockets for space travel after the Second World War gave rise to the expression not rocket science to suggest that something is not really very difficult. Rocket meaning ‘a reprimand’, as in to give or get a rocket, is Second World War military slang—the first recorded example is stop a rocket. The salad vegetable rocket [M16th] is a totally different word, which came via French roquette from Latin eruca, meaning a kind of cabbage.