A venomous animal delivers its toxin actively — by biting, stinging or spearing. A poisonous one is harmful passively, when eaten or touched. The rule of thumb: if it bites you and you die, it is venomous; if you bite it and you die, it is poisonous.
The core difference
Both involve toxins. The difference is entirely in delivery.
- venomous — injects toxin: snakes, scorpions, jellyfish, some spiders.
- poisonous — toxic on contact or ingestion: poison dart frogs, death cap mushrooms, pufferfish.
The awkward cases
Some animals are both. Certain snakes are venomous when they bite and also poisonous to eat. And a few species are neither in the strict sense but toxungenous — they spray or spit toxin without injecting it, which is what spitting cobras do.
Why the distinction is worth keeping
Because it tells you what the risk actually is. Calling a snake poisonous suggests it is dangerous to handle or eat; calling it venomous tells you the danger is the bite. In field or safety writing that is not a nicety.
