We’re pretty sure you wouldn’t drink a mysterious substance labeled “poisonous snake venom,” even if you didn’t know the meaning of venom. However, just to be clear, venom means "poison." Stay away from it.
Venom is poisonous fluid produced by animals such as snakes, spiders, and certain people. Okay — we take that last one back, sort of. Scientifically speaking, people don’t produce venom, but they can certainly do so in a metaphorical sense. That’s why venom can also be used to mean “malice” or “hatred.” If you encounter someone who seems full of venom, remember that kindness can be a good antidote. (So can a really insulting remark.)