Toad is one of Princess Peach’s most loyal subjects. He acts as an advisor to Mario in several of the games.
His name is a short form of toadstool, a term used to describe mushrooms with large caps where toads would sit.
Toad’s red and white head make him look like the fly agaric mushroom. In some cultures, this mushroom is viewed as a symbol of good luck, an ingredient in ancient ritual drinks or a hallucinogen.