Origin and Etymology of rheum
Middle English reume, from Anglo-French, from Latin rheuma, from Greek, literally, flow, flux, from rhein to flow — more at stream
First Known Use: 14th century
Medical Definition of Rheum
: a genus of Asian herbs (family Polygonaceae) that have large leaves, small flowers, and a 3-winged fruit and that include the rhubarbs (as the Chinese rhubarb, R. officinale, and rhapontic, R. rhaponticum)
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