Friday the 13th
Many believe Friday the 13th is the unluckiest day of the year. There are many superstitions and myths surrounding the day. Reuters/Ali Jarekji

Friday, the 13th, is surrounded by many superstitions and unexplainable fears. One such phobia is the fear of the day itself, which is called paraskevidekatriaphobia.

Paraskevidekatriaphobia is derived from the Greek words Paraskeví (Friday), dekatreís (13) and phobía (fear).

According to psychotherapist Donald Dossey of the Stress Management Center-Phobia Institute in Ashville, N.C., people with paraskevidekatriaphobia have a blind, unreasoning fear of this day and date, as opposed to those who have a clear, reasonable fear of not being able to say that word.

The Institute's Web site stated that Dossey tells his patients, Paraskevidekatriaphobia -- when you learn to pronounce it, you're cured!

Here are 10 other phobias that you probably cannot pronounce:

1. Friggatriskaidekaphobia: also the fear of Friday, the 13th. It derives from the words Frigga, which is the name of the Norse goddess for whom Friday is named and triskaidekaphobia, which means fear of the number 13.

2. Kakorraphiaphobia: fear of failure.

3. Arachibutyrophobia: fear of peanut butter sticking to the roof of your mouth.

4. Giraffeophobia: fear of sticking your neck out.

5. Hexakosioihexekontahexaphobia: fear of 666.

7. Psellismophobia: fear of stuttering.

8. Aichmophobia: a morbid fear of sharp objects.

9. Spheksophobia: fear of wasps.

10. Sesquipedaliophobia: fear of long words.