Word Study
saponin
CIDE DICTIONARY
saponin, n. [L. sapo, -onis soap: cf. F. saponine.].
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. [1913 Webster]
OXFORD DICTIONARY
saponin, n. any of a group of plant glycosides, esp. those derived from the bark of the tree Quillaja saponaria, that foam when shaken with water and are used in detergents and fire extinguishers.
Etymology
F saponine f. L sapo -onis soap
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