What is pertaining to, or obtained from, the poppy or opium; specif. (Chem.), designating an acid related to aconitic acid, found in opium and extracted as a white crystalline substance called?

meconic — Pertaining to, or obtained from, the poppy or opium; specif. (Chem.), designating an acid related to aconitic acid, found in opium and extracted as a white crystalline substance. (Webster's 1913.)

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