An octopus was a type of cephalopod native to Earth, related to squid and cuttlefish. Some Human cuisines included octopus.
Malcolm Reed once told his sister Madeline that he liked to eat octopus, especially the little suction cups. She thought he was joking though. (ENT: "Silent Enemy")
Brad Boimler's 2381 holonovel Crisis Point II: Paradoxus included the character of Koro, a giant sentient octopus who was a Federation ambassador. (LD: "Crisis Point 2: Paradoxus")