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Medical Dictionary

arsenic trioxide

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noun ar·se·nic trioxide \ˌärs-nik-, -ən-ik-\

Medical Definition of arsenic trioxide

  1. :  a poisonous trioxide As2O3 or As4O6 of arsenic that was formerly used in medicine and dentistry but has been abandoned for therapeutic purposes and is now used especially as an insecticide and weed killer—called also arsenic, arsenious acid, arsenious oxide, white arsenic




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