Dr. Dawn Ruben "Snakes are not poisonous and frogs are not venomous. Venom is a toxic substance that is injected. Certain species of snakes, scorpions and spiders are venomous, not poisonous...A poison is a substance that is absorbed through the skin or ingested, resulting in toxicity. Certain amphibians, fish and insects secrete a substance that is poisonous. The poisonous animal does not inject the substance into another creature."
This is off the San Diego zoo site in the children's questions section "First, there’s technically a difference between poisonous and venomous. Poisonous means that something is toxic if it is swallowed or absorbed. Venomous describes an animal that injects toxic venom into another animal, usually with teeth or fangs but sometimes with spines or spurs."
and this is off The American Board of Veterinary Toxicology website.
"A note about the difference between the terms POISONOUS and VENOMOUS. A mistake is commonly made using either of these terms interchangeably. While related, these terms have distinctive, unique meanings. A poisonous animal or plant contains a toxic substance within it constituent parts or on its surface. Poisonous is the term that describes the majority of plant derived toxins as well as polar bear liver (vitamin A), poison arrow frogs or toads. The term venomous means that the organism has a toxic substance and a specialized organ for delivering this substance. Some examples of venomous animals and their venom delivery apparatus are bees <the stinger>
venomous snakes <the hollowed fang> scorpions <the stinger>."