Hippophobia
Short for hippopotomonstrosesquippedaliophobia also known as the fear of long names
Person 1: I fear long words
Person 2: Hmm, it appears you have hippophobia
Person 1: I have what?
Person 2: Hippophobia is short for hippopotomonstrosesquippedaliophobia
Person 1: OH JESUS CHRIST THE HORROR
Person 2: Hmm, it appears you have hippophobia
Person 1: I have what?
Person 2: Hippophobia is short for hippopotomonstrosesquippedaliophobia
Person 1: OH JESUS CHRIST THE HORROR