ratsbane Meaning, Definition & Usage

  1. noun a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer
    arsenous oxide; arsenous anhydride; white arsenic; arsenic; arsenic trioxide.

WordNet

Rats"bane noun
Etymology
Rat + bane.
Definitions
  1. Rat poison; white arsenic.

Webster 1913