There are many, many strange things about the octopus.
- They have three hearts.
- They're the only invertebrates capable of using tools.
- They can open childproof pill bottles.
But here is the strangest:
There are three plural forms of octopus:
octopuses, octopi, and octopodes
- Currently, octopuses is the most common plural form in the US as well as the UK.
- Octopodes is rarely used but perfectly acceptable.
- Octopi is frequently used but considered incorrect by most grammarians.