The fear of Friday the 13th is called
paraskavedekatriaphobia,a word derived from the concatenation of the Greek words Paraskeví(Παρασκευή) (meaning Friday), and dekatreís (δεκατρείς) (meaning thirteen), attached to phobía (φοβία) (meaning fear).
This is a specialized form of triskaidekaphobia, a simple phobia (fear) of the number thirteen, and is also known as friggatriskaidekaphobia. The term triskaidekaphobia was derived in 1911 and first appeared in a mainstream source in 1953.....
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