Definition: The word "Arachnid" in Greek means "snail." It refers to a group of animals that are known for their sharp claws and webbed tentacles. Definition: The group of arachnids, which includes spiders, scorpions, and lizards, is known for their venomous bites. These creatures have evolved from prehistoric reptiles and include some of the most fearsome snakes in the world. They are classified into different orders based on their anatomy and behavior, with the largest being the Arachnida (snail-like) order.