The Collaborative International Dictionary of English v.0.48:

Chiretta \Chi*ret"ta\, n. [Hind. chir[=a][imac]t[=a].]
   A plant (Agathotes Chirayta) found in Northern India,
   having medicinal properties to the gentian, and esteemed as a
   tonic and febrifuge.
   [1913 Webster]