Underwater Vehicle Uses a Balloon To Dart Like an Octopus
Zothecula writes When you inflate a balloon and then release it without tying the valve shut, it certainly shoots away quickly. Octopi utilize the same basic principle, although they suck in and then rapidly expel water. An international team of scientists have now replicated that system in a soft-bodied miniature underwater vehicle, which could pave the way for very quickly-accelerating full-size submersibles.
Octopus is English, derived from Greek. All three plurals are in current use, and it is usage, not etymology, that defines what is "correct".