It’s a phobia and it relates to this Friday. It’s a long long word.
Friday is Friday the 13th. It is one of two on the calendar this year. The other comes up in October. So, what phobia do you have if you fear Friday the 13th? It's called, Paraskavedekatriaphobia. Say that three times!!!!
Here is the definition from Etymology Nerd.
Occasionally it'll take the form friggatriskaidekaphobia, but that's rarer. Here, we analyze the term paraskavedekatriaphobia, or "the fear of Friday the 13th". The first element, paraskavei, is the Greek term for "Friday" and in Ancient Greek literally meant "day of preparation" as paraskeue. This in turn is a portmanteau of para-, meaning "half", and skeue, meaning "dress". After all, while you're preparing, you're only half-dressed. The second element, dekatreis, is Greek for "thirteen", and is composed of deka-, or "ten" (from Proto-Indo-European dekm, which may be connected to komt, "hand"), and tris, or "three" (also PIE). Finally, phobia is from phobos ("fear"), from phebomai ("to flee"; makes sense), from PIE bhegw, "to run". So, what today means "fear of Friday the Thirteenth" can be broken up into five Greek words meaning "half-dressed three-hand running"!
Where did the fear come from?
Historians believe the fear of Friday the 13th may be rooted in Christianity. Jesus was crucified on a Friday and 13 guests were believed to be at the last supper. Historians also believe that 13th guest was Judas, who betrayed Jesus.
Here are some superstitions involving Friday the 13th.
1. They say you should not get your haircut on a Friday the 13th because it will result in a family member death.
2. Three things you should not do on Friday the 13th: put your shoes on a table, sleep on a table, or sing at the table. The superstitious say doing any of those will increase your risk of bad luck.
3. The superstitious believe ships that set sail on Fridays are doomed to misfortune. A similar myth holds that all trips began on Friday will encounter bad luck.
4. Knocking over the salt is thought to lead to bad luck on Friday the 13th.
5. Rumor has it, if you walk under a ladder it will lead to your own hanging. The myth dates back to the medieval age. Good news: you might be able to avoid it if you say “bread and butter” as you walk under. If you have already done it, try crossing your fingers until you see a dog.
On that note, good luck Friday.