@renissance1 @myownpetard @jamdoodles I didn't think about this before, so I was curious. There seem to be a lot of options!
Wiktionary says: octopus (plural octopuses or octopusses or octopi or octopodes or octopii) (see usage notes)
I highly recommend reading these usage notes, they are very interesting:
https://en.m.wiktionary.org/wiki/octopus