The fear of Friday the 13th is called paraskavedekatriaphobia (a word that is derived from the concatenation of the Greek words Παρασκευή, δεκατρείς, and φοβία, meaning Friday, thirteen, and phobia respectively; alternative spellings include paskevodekatriaphobia or paraskevidekatriaphobia, and is a specialized form of triskaidekaphobia, a phobia (fear) of the number thirteen.
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