Wiktionary
n. An enormous squid, of the subfamily ''(taxlink Taoniinae subfamily)'', of which few specimens have been studied.
Wikipedia
The colossal squid (Mesonychoteuthis hamiltoni, from Greek mesos (middle), onycho (claw, nail), and teuthis ( squid)), sometimes called the Antarctic or giant cranch squid, is believed to be the largest squid species in terms of mass. It is the only known member of the genus Mesonychoteuthis. It is known from only a few specimens, and current estimates put its maximum size at long and weighing possibly up to 750 kg (1,650 lb), based on analysis of smaller and immature specimens, making it the largest known invertebrate.
Usage examples of "colossal squid".
For the moment I turned the corner of the deckhouse and had an unobstructed view astern, there it was -- apparently two full moons rising close over the stern of the ship and lighting the decks and rigging with a sickly yellow glow -- the eyes of the colossal squid.