From Middle English rubarbe, from Old French, from Late Latin reubarbarum, from Latin Rha (“River Volga”) (in the region from which the plant came to the Mediterraneum, cognate with New Latin Rheum) + barbarum (“barbarian”)
- Any plant of the genus Rheum, especially Rheum rharbarbarum, having large leaves and long green or reddish acidic leafstalks, that are edible, in particular when cooked (although the leaves are mildly poisonous).
- The dried rhizome and roots of Rheum palmatum or Rheum officinale, from China, used as a laxative and purgative.
- A word repeated softly to emulate background conversation. (see rhubarb rhubarb).
- An excited, angry exchange of words, especially at a sporting event.
- (baseball) A brawl.
- (military) An RAF World War II code name for operations by aircraft (fighters and fighter bombers) seeking opportunity targets.
For usage examples of this term, see Citations:rhubarb.