What does cephalopod mean?
A cephalopod is any marine mollusc belonging to the class Cephalopoda, a group defined by a prominent head ringed by tentacles or arms attached directly to it — the very feature its Greek-derived name describes ('head-foot'). The class includes some of the ocean's most familiar and fascinating animals: octopuses, squids, cuttlefish, and the chambered nautilus. Cephalopods are renowned for their remarkable adaptations: they can rapidly change colour and skin texture for camouflage and communication, propel themselves through water by jet propulsion, and, in many species, squirt ink to evade predators. They also possess sophisticated nervous systems and large eyes, with the octopus widely regarded as among the most intelligent of all invertebrates. The word appears chiefly in zoology, marine biology, and popular science writing, and its plural is simply 'cephalopods'.
nounAny marine mollusc of the class Cephalopoda, characterised by a prominent head, large eyes, and tentacles or arms surrounding the mouth, including octopuses, squids, cuttlefish, and nautiluses.
- A marine mollusc of the class Cephalopoda, such as an octopus, squid, or nautilus.
"The octopus is perhaps the most intelligent cephalopod known to science."
"Scientists have long marvelled at the problem-solving abilities of the common octopus, a remarkably clever cephalopod."
"The fossil record shows that cephalopods once dominated the ancient seas hundreds of millions of years ago."
Regular English plural; no irregular form exists.
"Cephalopods are found in every ocean on Earth, from shallow reefs to the deep sea."
Cephalopods can change the colour and even texture of their skin in a fraction of a second — despite being almost certainly colourblind.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of cephalopod
The word 'cephalopod' derives from modern Latin 'Cephalopoda', itself formed from the Ancient Greek 'kephalē' meaning 'head' and 'pous' (stem 'pod-') meaning 'foot' — a reference to the arms and tentacles that appear to spring directly from the animal's head. It entered English usage in the early nineteenth century as naturalists formalised their classification of these animals.
Related word forms
How cephalopod is actually used
A scientific and zoological term, used in both technical literature and popular nature writing; plural is 'cephalopods'.