No, this word does not mean a four footed hippopotamus, what is does mean is pertaining to a very long word. Antidisestablishmentarianism is hippopotomonstrosesquipedalian, but is outdone by floccinaucinihilipilification by one letter. These words exist just so someone can use them to show that they know a very long word. Once you figure out that other than impress the illiterate they have few, if any, other uses, they lose their mystique and become pretty ordinary.
When playing Scrabble, I always lost to my children because I would be trying to make some long word and they kept playing three and four letters. My efforts could be said to be ficulnean.
The Lost Day — A Short Short Story - Lost Day
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