Octopus - Etymology and Pluralization

Etymology and Pluralization

The term "octopus" is from Greek ὀκτάπους (oktapous, "eight-footed"), with traditional plural forms "octopuses" (pronounced /ˈɒktəpʊsɪz/) from English grammar and "octopodes" (pronounced /ɒkˈtɒpədiːz/) from the Greek. Currently, "octopuses" is the most common form in both the US and the UK. The term "octopod" (plural: "octopods" or "octopodes") is taken from the taxonomic order Octopoda, but has no classical equivalent. The collective plural "octopus" is usually reserved for animals consumed for food.

Some authorities consider "octopi" an objectionable hypercorrection, feeling the form arose from the incorrect assumption that "octopus" is a Latin second-declension form. However, "octopus" is a scientific Latin third-declension noun with a plural of octopodes. Nevertheless, the Oxford English Dictionary (2008 Draft Revision) lists "octopuses", "octopi", and "octopodes" (in that order), labelling "octopodes" 'rare' and noting that "octopi" derives from the misapprehension that octōpus is a second-declension Latin noun. The book further maintains that if the word were native to Latin, it would be third declension octōpēs (plural: octōpedes) after the pattern of pēs ("foot", plural pedēs). The original Latin word for octopus and other similar species is polypus, from Greek polýpous (πολύπους, "many-footed"); again, usually the inappropriate plural polypī is used instead of polypodēs.

Fowler's Modern English Usage states, 'the only acceptable plural in English is "octopuses"', that "octopi" is 'misconceived', and "octopodes" 'pedantic'. Chambers 21st Century Dictionary and the Compact Oxford Dictionary list only "octopuses", although the latter notes that "octopodes" is 'still occasionally used'. The descriptivist Merriam-Webster 11th Collegiate Dictionary lists "octopuses" and "octopi" in that order; likewise, Webster's New World College Dictionary lists in order "octopuses", "octopi", and "octopodes".

In modern Greek, the word is χταπόδι (khtapódi; plural: χταπόδια, khtapódia), from Byzantine ὀκταπόδιον (oktapódion) derived from the Classical Greek variant ὀκτάπους (oktápous).