Octopus (Melinda Riger / G B Scuba)


The correct plural of ‘octopus’ is a singular mystery wrapped in tentacles and hidden beneath a rock. Shall we have the grammatical discourse first, or save it for later? Let’s have some octopi  octopuses octopodes to look at first… [oh, and it’s definitely not ‘octopussies’, not even for 007] 

 Melinda Riger GRAND BAHAMA SCUBAOctopus 2 ©Melinda Riger GB Scuba


  • Their 8 ‘arms’ come in pairs ( the back two act more like legs) and they are bilaterally symmetric
  • Their beak is hard, but they have no internal or external skeleton (so they can squeeze into tight crannies)
  • They paralyse their prospective meals with saliva from their beak; or drill holes in molluscs, stun them with venom and rip them out
  • They defend themselves with squirted ink, jet propulsion, camouflage or venom
  • All species are venomous; only one species is deadly to humans (not found in the Bahamas)
  • They are able to detach an arm (autotomy) to distract predators with the wriggling shed limb
  • The male’s 3rd right arm is the one used for reproduction… (stop giggling at the back)
  • Well, you asked: 1. special hidden extra arm 2. packets of sperm 3. into the female’s ‘mantle cavity’
  • No, I don’t know any more than that – ask your father.
  • Oh, and the males tend to die within months of mating, deftly using death to sidestep parenting 8-limbed offspring
  • They are unlikely to make a good pet for your family. Those who try, fail
  • They are eaten throughout the world, sometimes alive (e.g. Korea)

Another photo of Melinda’s, showing how an octopus can tuck itself away inside a small gap in the rocks.  It can still keep an eye on you, thoughOctopus ©Melinda Riger GB Scuba


There’s much debate about this comparatively unimportant question. Not even an octopus would care. The viable candidates are: octopuses; octopodes; and octopi.  Since all are in common usage, none is ‘wrong’, though some are more correct than others…

1. OCTOPUSES An anglicised grammatical progression of a latin-sounding word to a logical plural, similar to ‘virus’ and viruses’. Only an extreme pedant would want to argue for ‘viri’ or ‘virii’. Similarly with bonus: “We all got boni for Christmas”. No, you didn’t. They were bonuses.

2. OCTOPODES the origin of ‘octopus’ is a Greek word ὀκτάπους, later latinised. The correct plural in Athens would have been ‘octopodes’. It is not derived from a 2nd declension latin noun, as often assumed, in which case the plural might indeed be ‘octopi’ (cf annus / anni; year / years). Using this etymologically accurate form in conversation might lead to a lonely life as people begin to move away from you. But you would still be in the right, if that matters to you so much…

3. OCTOPI see above. In a picky world, this is the least correct of the 3, being a pluralisation based on the wrong root origin (i.e. on latin, not greek), and therefore etymologically unsound. In practice, it’s quick and easy, and everyone knows what you mean, which is largely the point of language, I guess. Personally, I’d use octopuses if I ever used the word.

SUMMARY: 2 is the most technically correct, and also the most likely to get you chucked off the side of the boat. Fully clothed. 1 is a logically correct anglicisation. 3 is a technically incorrect form, but long usage has made it acceptable to all but verbal Luddites. Push them off the boat too.

If you bothered to plough through that, you deserve some quality recreation. Even if you gave up in despair, you deserve these 2 videos (both taken in the Bahamas), which show the incredible way that these creatures move. Those who have never seen a live octopus will be amazed at their bodily transformations. If you only have time for one, see the top one – professionally done, and shorter. The lower one is a good amateur video, with a certain amount of diver  heavy breathing and gurgling.



ADDENDUM This was never going to be easy! What about ‘cactus / cacti’, do I hear? Yes, cactus was known to Greeks as κάκτος (kaktos); but it was equally known to the Romans as ‘cactus’, not as a word that had to be imported by them from the Greeks and adapted. So the word’s root is as much latin as greek. No doubt that explains similar latin-origin ‘i’ plurals such as alumnus / alumni and stimulus / stimuli.

While fact-checking – a rare pleasure for me – I discovered a cheerful ‘Merriam-Webster’ video dealing authoritatively with the vexed ‘octopus plural’ debate (best skip the terrible ad)


Octopus (Adam Rees)