Here’s a quick one for you.
The fear of Friday the 13th is called paraskevidekatriaphobia, 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). The term triskaidekaphobia derives from the Greek words “tris”, meaning ‘three’, “kai”, meaning ‘and’, and “deka”, meaning ‘ten’. the whole word means three and ten. The word was derived in 1911 and first appeared in a mainstream source in 1953.