The Collaborative International Dictionary of English v.0.48:
Chay root \Chay" root`\ [Tamil sh[=a]ya.] The root of the Oldenlandia umbellata, native in India, which yieds a durable red dyestuff. [Written also choy root.] [1913 Webster]The Collaborative International Dictionary of English v.0.48:
Choy root \Choy" root`\ (choi" r[=oo]t`). See Chay root. [1913 Webster]