Definition of octopus in English:



  • A cephalopod mollusc with eight sucker-bearing arms, a soft sac-like body, strong beak-like jaws, and no internal shell.

    Order "Octopoda", class "Cephalopoda": "Octopus" and other genera

    • ‘This fish is vital to the reef ecosystem as a predator of smaller fish, lobster, crab, octopus, and shrimp.’
    • ‘The harbor seal's diet consists of fish, cephalopods, such as octopus and squid, and crustaceans.’
    • ‘Abalone belongs to the phylum Mollusca, a group which includes clams, scallops, sea slugs, octopuses, and squid.’
    • ‘Cephalopods, the octopus, the squid and cuttlefish are the main groups, I think.’
    • ‘The most obvious example is the mantle, a spherical bag of hydrostat in an octopus and a cylinder closed at one end in a squid.’
    • ‘The task of retrieving the prey proved too simple for the octopus, so it was given a jar of fish with a screw-cap lid.’
    • ‘He compares the octopus to the other cephalopods - cuttlefish, crayfish, and the like.’
    • ‘The olives were too strong, and the octopus too hesitant.’
    • ‘Indeed, octopuses are frequently observed to exert force on objects with their arms aligned parallel to the line of force.’
    • ‘A nautilus does not have suckers on its tentacles like an octopus does.’
    • ‘Giant cephalopods such as squid and octopuses are also a great source of sea-monster folklore.’
    • ‘Local fishermen reported the appearance of large numbers of octopuses.’
    • ‘What are the implications of the physical properties of water for suction attachment in octopus suckers?’
    • ‘The major group of mesozoans, the Dicyemida, live as microscopic parasites in the renal organs of squid and octopuses.’
    • ‘In addition, the octopus can inject a powerful neurotoxin that is stored in the salivary glands to disable or kill its prey.’
    • ‘The circulatory systems of other vertebrates, as well as those of squids and octopuses, employ similar rubbery materials.’
    • ‘They eat a wide range of prey, often octopus and small molluscs.’
    • ‘Otters also are known to eat crabs, octopus, squid, sea stars, and fish.’
    • ‘With more than a 250 species, octopuses are members of an ancient group of animals called cephalopods.’
    • ‘Cephalopods, which includes octopuses and squid, have seriously weird brains.’


The standard plural in English of octopus is octopuses. However, the word octopus comes from Greek and the Greek plural form octopodes is still occasionally used. The plural form octopi, formed according to rules for some Latin plurals, is incorrect


Mid 18th century: modern Latin, from Greek oktōpous (see Octopoda).