arsenic
ar-se-nic
noun
A highly toxic compound, often arsenic trioxide, used as a poison.
"The detective suspected arsenic was used."
noun
A brittle, greyish-white, highly poisonous chemical element (As).
"Arsenic is a metalloid element."
Thesaurus
Synonyms: atomic number 33, As, ratsbane, arsenous anhydride, white arsenic, arsenic trioxide, arsenous oxide