a tall, hairy European perennial plant (Inula helenium) of the composite family, having flower heads with many slender, yellow rays: naturalized in the NE U.S.
See elecampane in American Heritage Dictionary 4
(ĕlˌĭ-kăm-pānˈ)
noun
A tall coarse plant (Inula helenium) native to central Asia, having rayed yellow flower heads. The roots are used medicinally.