senna Meaning, Definition & Usage

  1. noun any of various plants of the genus Senna having pinnately compound leaves and showy usually yellow flowers; many are used medicinally

WordNet

Sen"na noun
Etymology
Cf. It. & Sp. sena, Pg. sene, F. séné; all fr. Ar. sana.
Definitions
  1. (Med.) The leaves of several leguminous plants of the genus Cassia. (C. acutifolia. C. angustifolia, etc.). They constitute a valuable but nauseous cathartic medicine.
  2. (Bot.) The plants themselves, native to the East, but now cultivated largely in the south of Europe and in the West Indies.

Webster 1913