TIL. I always thought that "If it bite you -> you die = venom" and "If you eat, bite, touch -> you die = poison". But your differentiation makes more sense
If a venomous snake bites you, you die. If you bite a venomous snake, you live. If a poisonous snake bites you, you will. If you bite a poisonous snake, you die.
Or Hamlet's mother died by drinking poisoned wine. Hamlet died by being stabbed with an envenomed sword.
That explains the words "venomous" and "poisonous" used of creatures.
It's different for the actual substances. Although it relates: a venomous creature that bites you will release its venom into your bloodstream.