Poisons work via touch, ingestion or inhalation. Venoms are injected via a bite or wound.
The earth is filled with creatures and plants that have evolved many and varied ways of gaining advantage over predators and prey. Poison and venom are among the most nightmare-inducing of these.
If you’re exposed to toxins, you probably don’t care whether it’s venom, poison, or something else, but we’re curious so we looked it up.
It turns out that the nature of exposure is the fundamental difference. Mental Floss explains it this way “Poisons work their deadly magic through touch, ingestion, or inhalation, while venoms are injected directly into a wound.”
Poison tends to be a defensive mechanism.
… poisonous organisms administer secretions passively, usually through their skin, when another creature touches or ingests it (think poison frogs).
Venom is typically used as a way to immobilize prey or an attacking predator.
…venomous creatures, such as wasps, deliver their toxic cocktails by wounding another animal, often via a fang, stinger, or spine.