Hippopotomonstrosesquippedaliophobia is the fear of long words. It's also referred to as sesquipedalophobia (a Latin term that means "long word"). When this phobia involves a fear of encountering a long word when reading aloud or in a social context, it can be considered a type of social phobia.

The fear of long words is very specific. Some people may fear long words with many syllables, while others fear obscure words. Some people might have an aversion to common words of moderate length.

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