Indigo plant Meaning, Definition & Usage

  1. noun deciduous subshrub of southeastern Asia having pinnate leaves and clusters of red or purple flowers; a source of indigo dye
    Indigofera tinctoria; indigo.

WordNet

Definitions
  1. (Bot.), a leguminous plant of several species (genus Indigofera), from which indigo is prepared. The different varieties are natives of Asia, Africa, and America. Several species are cultivated, of which the most important are the I. tinctoria, or common indigo plant, the I. Anil, a larger species, and the I. disperma.

Webster 1913