angostura bark

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The bitter aromatic bark of either of two South American trees, Galipea officinalis or Cusparia trifoliata (both sometimes placed in the genus Angostura), used as a flavoring in bitters and as a tonic.

from The Century Dictionary.

• noun See bark.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the bitter bark of a South American tree; used in medicines and liqueurs and bitters