1. Any of several plants of the genus Rheum, especially R. rhabarbarum, having long edible green or reddish leafstalks that are usually cooked and sweetened. Also called pie plant.
2. A preparation made from the dried rhizomes and roots of any of several plants of the genus Rheum, especially R. palmatum or R. officinale of East Asia, used as a laxative.
3. Informal A quarrel, fight, or heated discussion.
[Middle English rubarbe, from Old French, from Late Latin reubarbarum, probably alteration (influenced by Greek rhēon) of rhabarbarum : rha, rhubarb (from Greek rhā, of Iranian origin; akin to Middle Persian rēwās and Pashto rawāš) + Latin barbarum, neuter of barbarus, barbarian, foreign; see BARBAROUS.]
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Indo-European & Semitic Roots Appendices
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