Quiz: What’s the name for the phobia of a naked mole rat? (National Zoo photo)

It’s a mouthful for a simple phobia: fear of Friday the 13th.

The names of conditions in which a sufferer is plagued by a persistent, irrational fear are usually derived from Greek words and not the easiest to get your mouth around. Don’t believe us? Try to pronounce the word for the fear of long words: Hippopotomonstrosesquipedaliophobia.

Some phobias have been well documented and are more easily understood, such as agoraphobia (fear of being in a place where escape is difficult), xenophobia (a fear of strangers), and claustrophobia (a fear of small spaces).

But there are hundreds of lesser known phobias that can be only be explained by filmmaker Alfred Hitchcock, the master of fear: “There is no terror in the bang, only in the anticipation.”

Here’s our round up of the five strangest phobias you never knew existed, and the famous faces we associate with them:

1. Dextrophobia: Fear of objects at the right side of the body.

We can’t help but think Beyonce was suffering from dextrophobia when she recorded “Irreplaceable.”

2. Clinophobia: Fear of going to bed

Hollywood’s younger generation seems to collectively suffer from clinophobia, but poor Lindsay Lohan — she really got the raw end of the deal.

3. Heliophobia: Fear of the sun.

I’ve never thought it would be easy to be Marilyn Manson. But to have to deal with a sun phobia too? We hope the inch-thick white skin powder shields a few of the rays.

4. Phronemophobia: Fear of thinking.

I can’t help wondering if this was a criteria used during the casting of Jersey Shore.

5. Rhytiphobia: Fear of getting wrinkles.

The Real Housewives of D.C., and all their fellow housewives nationwide, must band together to beat this disease. Maybe a run to prevent rhytiphobia? A wrinkly ribbon we can all pin to our shirts?

And now, our bonus round of two phobias impossible to pair with a famous face...

Pteronophobia, or a fear of being tickled by feathers. And zemmiphobia, or a fear of the Great Mole Rat.

Check out the list of phobias and let us know what you're afraid of in the comments, or by using #Friday13fears on Twitter, and we’ll post your phobias back here.

TERRIFYING Taphophobia - fear of being buried alive #friday13fearsless than a minute ago via web Favorite Retweet ReplyBeverly Lambert

Our hearts go out to all those suffering from Paraskevidekatriaphobia today http://wapo.st/jevUxY #Friday13fearsless than a minute ago via web Favorite Retweet ReplyRx Mosaic Health