Squidward from Spongebob Squarepants is an octopus, not a squid.
Yes, his name is rather counterintuitive, but the show’s creator, Stephen Hillenburg, asserts that Spongebob’s cranky neighbor is definitely an octopus (someone really ought to straighten this out with his voice actor though...) Another fact that settles this debate is that Squidward possesses an octopus’s rounded head, not the distinctive pointy mantle of a squid.
As for his misleading name, honestly...would “Octoward” Tentacles have a better ring to it?? Although, if you really think about it, we should technically be calling Squidward a ‘hexapus’ since he only has six legs and not the usual eight! Hillenburg said this choice was made to keep the character from appearing too bulky and burdened.