\Es"er*ine\ (?; 104), n. [From native name of the
Calabar bean: cf. F. ['e]s['e]rine.] (Chem.)
An alkaloid found in the Calabar bean, and the seed of
{Physostigma venenosum}; physostigmine. It is used in
ophthalmic surgery for its effect in contracting the pupil.