• WordNet 3.6
    • n saponin any of various plant glucosides that form soapy lathers when mixed and agitated with water; used in detergents and foaming agents and emulsifiers
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Webster's Revised Unabridged Dictionary
    • n Saponin (Chem) A poisonous glucoside found in many plants, as in the root of soapwort (Saponaria), in the bark of soap bark (Quillaia), etc. It is extracted as a white amorphous powder, which occasions a soapy lather in solution, and produces a local anæsthesia. Formerly called also struthiin quillaiin senegin polygalic acid, etc. By extension, any one of a group of related bodies of which saponin proper is the type.
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Century Dictionary and Cyclopedia
    • n saponin A glucoside (C32H54O18) found in the root of Saponaria officinalis and many other plants. It is a powerful sternutatory.
    • n saponin A general name applied to glucosides similar to saponin (see def. 1) which yield a foam or lather when the aqueous solution is shaken. Smilacin is a saponin. The poisonous saponins are called sapotoxins.
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Chambers's Twentieth Century Dictionary
    • n Saponin a vegetable principle, the solution of which froths when shaken, obtained from soapwort, &c
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Webster's Revised Unabridged Dictionary
L. sapo, -onis, soap: cf. F. saponine,
Chambers's Twentieth Century Dictionary
L. sapo, saponis, soap.


In literature:

Saponin was found in all parts of the plant.
"Scientific American Supplement, No. 623, December 10, 1887" by Various
The saponins constitute a group of glucosides which are widely distributed in plants, whose properties have been known since early Grecian times.
"The Chemistry of Plant Life" by Roscoe Wilfred Thatcher
It gives no tannin or saponin tests.
"The Nature of Animal Light" by E. Newton Harvey

In news:

Anti-Wrinkle Activity of Hydroyzed Ginseng Saponins.
Anti-Wrinkle Activity of Hydroyzed Ginseng Saponins
The reason for washing quinoa before cooking is to rinse off the saponins, which are a slightly soapy tasting phytochemical.