phar·ma·cog·no·sy 
(fär′mə-kŏgnə-sē)
(fär′mə-kŏgnə-sē)n.
The branch of pharmacology that deals with drugs in their crude or natural state and with medicinal herbs or other plants.
[PHARMACO- + Greek gnōsis, knowledge; see GNOSIS.]
phar′ma·cogno·sist n.
phar′ma·cog·nostic (-kŏg-nŏstĭk) adj.