hippopotomonstrosesquipedaliophobia /ˌhɪ.pəˌpɒ.tə(ʊ)ˈmɒn.stɹə(ʊ)ˌsɛs.kwɪ.pɪˌdɑːl.ɪ.ə(ʊ)ˈfəʊ.bɪ.ə/ noun1 •(humorous) The fear of long words.Ben suffers from hippopotomonstrosesquipedaliophobia, so he seldom uses words of more than three syllables.