One of the longest words in the dictionary is also the phobia of long words.
by Rachel McKittrick 12/19/2021
The Etymology
Adam Aleksic from The Etymology Nerd has the breakdown of the word Hippopotomonstrosesquipedaliophobia. First, we have the word hippo- meaning hippopotamuses, and monstro for monsters. Aleksic explains that these two words were probably meant to blow the word out of proportion and that they aren’t actually needed for the meaning of the word. The word sesquipedalis means “a foot and a half long”, (However, Merriam-Webster dictionary defines sesquipedalian as 1. having many syllables: Long, 2. given to or characterized by the use of long words) therefore sesquipedaliophobia is really all that is needed to make the phobia complete.
“It’s pretty evil to make people afraid of length fear another eighteen inches and thrice as many letters” — Aleksic
Merriam-Webster does go on to include that the ancient Roman poet, Horace cautioned young poets against using sesquipedalia Verba — “words a foot and a half long” which can be found in his book Ars Poetica.