An octopus has eight legs, but they are more commonly referred to as tentacles. The name "octopus" is directly derived from the prefix "oct-" which means eight and is found in other words such as "octagon."
On each of the octopus' legs are suction cups that help the animal attach itself to surfaces. When threatened by predators, the octopus releases a stream of black ink that disrupts vision in the water and allows the octopus to flee. The octopus' squishy body allows it to hide in crevices that are unreachable by most ocean animals. If a predator happens to catch one of the octopus' legs, it can detach it and regenerate it again without any permanent damage.