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(n.)
A peculiar bitter orange-brown substance, with strong, penetrating odor, found in two sacs between the anus and external genitals of the beaver; castor; -- used in medicine as an antispasmodic, and by perfumers.
  

N
castor| aromatic secretion obtained from beaver used medicinally

CASTOREO

castoreum, castorei
n. n. castor, aromatic secretion obtained from beaver used medicinally; 

See more at Wikipedia.org...

(n.)
A peculiar bitter orange-brown substance, with strong, penetrating odor, found in two sacs between the anus and external genitals of the beaver; castor; -- used in medicine as an antispasmodic, and by perfumers.
  

N
castor| aromatic secretion obtained from beaver used medicinally

CASTOREO

castoreum, castorei
n. n. castor, aromatic secretion obtained from beaver used medicinally;