venom

Any of various poisonous substances secreted by certain snakes, spiders, scorpions, and insects and transmitted to a victim by a bite or sting. Venoms are highly concentrated fluids that typically consist of dozens or hundreds of powerful enzymes, peptides, and smaller organic compounds. These compounds target and disable specific chemicals in the victim, damaging cellular and organ system function. Snake venoms, for example, contain substances that block platelet aggregation (causing bleeding) and that prevent the release of acetylcholine by nerve endings (causing muscle paralysis). Many substances contained in venoms are under investigation for use as pharmaceuticals.