> Octopus entered English from scientific Latin. In which the Greek plural was not used
The Latin (nominative) plural is octōpodēs, the Greek (nominative non-neuter) plural is ὀκτώποδες. Almost identical. octopi is not used in Latin, it only appears to occur in English texts.
Most Romance languages get their primary word for "octopus" from an alternative Latin word for it, polypus (plural polypī), which comes from Greek πολύπους (plural πολύποδα). polypus is also an alternative word for octopus in English, albeit it is rather archaic. The English plural polypi cannot be accused of being a hypercorrection, but (for octopuses) polypuses is much more common. polypus is also medical terminology for a type of blood clot, and the polypi plural is often preferred when the word is used in that medical sense.
The usual Dutch word for "octopus", octopus, is pluralised by the standard Dutch rules, octopussen. English appears to be the only language in which this hypercorrect pseudo-Latin plural has any popularity.
The Latin (nominative) plural is octōpodēs, the Greek (nominative non-neuter) plural is ὀκτώποδες. Almost identical. octopi is not used in Latin, it only appears to occur in English texts.
Most Romance languages get their primary word for "octopus" from an alternative Latin word for it, polypus (plural polypī), which comes from Greek πολύπους (plural πολύποδα). polypus is also an alternative word for octopus in English, albeit it is rather archaic. The English plural polypi cannot be accused of being a hypercorrection, but (for octopuses) polypuses is much more common. polypus is also medical terminology for a type of blood clot, and the polypi plural is often preferred when the word is used in that medical sense.
The usual Dutch word for "octopus", octopus, is pluralised by the standard Dutch rules, octopussen. English appears to be the only language in which this hypercorrect pseudo-Latin plural has any popularity.