Physostigma
/ˌfʌɪsəʊˈstɪɡmə/Botany
noun
An African vine of the genus Physostigma (family Fabaceae (Leguminosae)), in which the style of the flower becomes inflated above the stigma, especially P. venenosum, the Calabar bean; (in form Physostigma) the genus itself. Also: a medicinal extract of the poisonous seed of P. venenosum, which contains the alkaloid physostigmine.
Origin
Mid 19th century. From scientific Latin Physostigma, genus name from physo- + stigma.