1. Any of various plants in the pea family, chiefly of the genera Senna and Chamaecrista, having pinnately compound leaves and showy, nearly regular, usually yellow flowers, used as ornamentals and for medicinal purposes.
2. A preparation of the dried leaves of Senna alexandrina, used as a laxative.
[New Latin, from Arabic sanā; akin to Aramaic sanyā, a thorn-bush.]
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Indo-European & Semitic Roots Appendices
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