saponin

n. group of glycosides found in plants (used in detergents and emulsifiers)

Saponins are glycosides of steroids, steroid alkaloids (steroids with a nitrogen function) or triterpenes found in plants, especially in the plant skins where they form a waxy protective coating. Some authors distinguish a third class of saponin, the alkaloid saponins. They dissolve in water to form a stable soapy froth; this is thought to be due to their amphiphilic nature. The word sapon means 'soap', referring to the permanent froth saponins make on being mixed with water.
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Saponin /sap·o·nin/ any of a group of glycosides widely distributed in plants, which form a durable foam when their watery solutions are shaken, and [more]Saponin - Community and Resources

Noun
1. any of various plant glucosides that form soapy lathers when mixed and agitated with water; used in detergents and foaming agents and emulsifiers
(hypernym) glucoside

n. saponin, group of glycosides found in plants (used in detergents and emulsifiers)