What does "alkaloid" mean?

Alkaloid: An organic base, especially one of a class of substances occurring ready formed in the tissues of plants and the bodies of animals. Note: Alcaloids all contain nitrogen, carbon, and hydrogen, and many of them also contain oxygen. They include many of the active principles in plants; thus, morphine and narcotine are alkaloids found in opium.

Additional senses

  1. 2.Pertaining to, resembling, or containing, alkali.

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