The following is a list of types of poison by intended use:

• Biocide – a chemical substance capable of killing living organisms, usually in a selective way
  • Fungicide – a chemical compound or biological organism used to kill or inhibit fungi or fungal spores
  • Microbicide – any compound or substance whose purpose is to reduce the infectivity of microbes
    • Germicide – a disinfectant
      • Bactericide – a substance that kills bacteria
      • Viricide – a chemical agent which "kills" viruses outside the body
  • Herbicide – a substance used to kill unwanted plants
  • Parasiticide – any substance used to kill parasites
  • Pesticide – a substance or mixture of substances used to kill a pest
    • Acaricide – pesticides that kill mites
    • Insecticide – a pesticide used against insects
    • Molluscicide – pesticides against molluscs
    • Nematocide – a type of chemical pesticide used to kill parasitic nematodes (roundworms)
    • Rodenticide – a category of pest control chemicals intended to kill rodents
• Spermicide – a substance that kills sperm