Word Study
cascara
CIDE DICTIONARY
cascara, n.
the dried bark of the cascara buckthorn used as a laxative; -- called also cascara sagrada . [WordNet 1.5]
OXFORD DICTIONARY
cascara, n. (in full cascara sagrada) the bark of a Californian buckthorn, Rhamnus purshiana, used as a purgative.
Etymology
Sp., = sacred bark
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