The octopus is a captivating creature, known for its three hearts, blue blood, and camouflage skills. This intelligent invertebrate presents a linguistic puzzle when referring to more than one of them. The question of the correct plural has led to confusion because the word’s ancient roots conflict with standard contemporary English rules. The answer is not as straightforward as simply adding an “s.”
The Three Acceptable Plural Forms
English often adopts foreign words and regularizes their pluralization, but “octopus” has resisted full standardization. The most common and widely accepted plural today is “octopuses.” This form follows the standard English convention of adding “-es” to nouns ending in “-us” and is the preferred plural in scientific and journalistic writing.
The second form, “octopi,” is familiar to the general public but is considered etymologically incorrect by many linguists. This plural stems from a mistaken application of Latin grammar rules. Despite its flawed origin, “octopi” remains in regular use and is listed as an acceptable alternative in many dictionaries.
The third and rarest plural is “octopodes,” which is the technically correct pluralization from the word’s original language. While uncommon in everyday speech, “octopodes” honors the word’s deepest linguistic history. All three forms—octopuses, octopi, and octopodes—are recognized as acceptable ways to refer to multiple animals.
The Linguistic Origin of the Plural Confusion
The trio of plurals stems from the word’s journey into English, which began in Ancient Greek, not Latin. The term “octopus” derives from the Greek compound word oktōpous, meaning “eight foot.” The proper Greek plural for a word ending in -pous would be -podes, which is the basis for the rare form “octopodes.”
Confusion began when English adopted the word from New Latin, where it had been Latinized. Because many English nouns ending in “-us” are derived from Latin, speakers incorrectly applied the Latin plural rule of changing “-us” to “-i.” This is why “octopi” became a popular, though incorrect, plural form.
The standard English plural, “octopuses,” emerged later in the 19th century. It treats “octopus” as a regular English noun, disregarding its complex classical etymology in favor of simplicity. The existence of three plurals is a direct result of English borrowing a Greek word, Latinizing it, and then applying its own modern rules.
Do Octopuses Even Gather in Groups?
The debate over the plural form is complicated by the animal’s biology, as octopuses are overwhelmingly solitary creatures. Most of the over 300 known species are territorial and prefer to live alone, only coming together briefly to mate. Encountering a true group of octopuses in the wild is rare, which reduces the practical need for a collective noun.
Because of this solitary nature, there is no widely accepted, formal collective noun for a group of octopuses, unlike a “school” of fish or a “pod” of whales. Playful suggestions like a “tangle” or a “consortium” hold no official standing in zoology. The plural form is therefore most often used when speaking generally about the species as a whole.
Recent scientific discoveries have challenged the notion of absolute solitude, particularly regarding the gloomy octopus (Octopus tetricus). Researchers observed high-density congregations in Jervis Bay, Australia, at sites nicknamed “Octopolis” and “Octlantis.” These areas saw up to 15 individuals living in close proximity, suggesting social behavior can emerge when resources are limited. These unusual “cities” remain rare exceptions to the general rule that the octopus is a loner.