Castor Oil
/ˈkæs.tər ɔɪl/noun
A pale yellow vegetable oil pressed from the seeds of the castor bean plant and used medicinally, industrially, and cosmetically.
Did you know?The name arose because castor oil was associated with castoreum, a pungent medicinal substance obtained from beavers, although modern castor oil comes entirely from a plant.
Etymological Timeline
Ancient Greek
Greek
κάστωρ (kástōr)
“Beaver; also the name of the mythological Dioscurus Castor”
Classical Latin
Latin
castor
“Beaver; the animal associated with castoreum”
Classical Latin
Latin
castoreum
“A pungent secretion from the beaver, used in medicine and perfumery”
Middle English
English
castor
“Beaver or castoreum; later applied to the castor-oil plant through association with beaver-derived substances”
18th Century
English
castor oil
“Oil from the seeds of the castor bean, named through its perceived connection with castoreum”
Modern English
English
castor oil
“Vegetable oil obtained from Ricinus communis seeds”
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