What is "calabar bean"

Calabar \Cal"a*bar\, n. A district on the west coast of Africa.

Calabar bean, The of a climbing legumious plant ( Physostigma venenosum), a native of tropical Africa. It is highly poisonous. It is used to produce contraction of the pupil of the eye; also in tetanus, neuralgia, and rheumatic diseases; -- called also ordeal bean, being used by the negroes in trials for witchcraft.

n. dark brown highly poisonous seed of the calabar-bean vine; source of physostigmine and used in native witchcraft [syn: ordeal bean]