- Specific, characterizable, poisonous chemicals, often proteins, with specific biological properties, including immunogenicity, produced by microbes, higher plants, or animals.
Definition from: MeSH via Unified Medical Language System at the National Library of Medicine
- A poison, usually protein, produced by higher plants, animals, or microorganisms that is toxic to other living organisms.
Definition from: CRISP Thesaurus via Unified Medical Language System at the National Library of Medicine
- A chemical, physical, or biological agent that causes disease or some alteration of the normal structure and function of an organism. Usually refers to poisonous substance produced during the metabolism and growth of certain microorganisms and some higher plant and animal species, or any poisonous isomer, homolog, or derivative of such a substance. It causes either permanent or reversible injury to the health of a living thing on contact or absorption, typically by interacting with biological macromolecules such as enzymes and receptors. Onset of effects may be immediate or delayed, and impairments may be slight or severe. (NCI)
Definition from: NCI Thesaurus via Unified Medical Language System at the National Library of Medicine
- A poison produced by certain animals, plants, or bacteria.
National Cancer Institute
Related discussion in the Handbook
See also Understanding Medical Terminology.