Many people live haunted by this concept of "fear". Fear of heights, fear of the dark, fear of spiders, fear of public speaking...you get the idea, and chances are, you probably have a couple of those extremely common fears (public speaking, for instance, continues to hold its top position as the number one fear in America). Though many of these fears seem widespread and therefore understandable to those who share them, there are a number of fears out there that are just plain...out there. So this week, I'm lightening the mood a little by presenting to you six of the most obscure fears in the world. Though odd, keep in mind that these things must be feared enough to gain them their own extraordinarily-long, scientific-y name.

1. Lutraphobia
Though the internet seems to be full of only adorable videos of these little critters swimming around,enough people do have a genuine fear of otters...at least, enough to gain the fear this interesting name.

2. Genuphobia
Bending from the knees and not the back might be the safest way to pick up heavy objects, but people with genuphobia would rather injure their spine than even think about those horrible, terrifying....knees.

3. Allodoxaphobia
Though human instinct naturally causes people to be opinionated, avoid speaking your mind around an allodoxaphobic. They won't criticize your opinion, they're just terrified of it.

4. Pteronophobia
Run! It's the tickle monster! Of course, this won't scare a pteronophobic, unless the tickle monster is carrying a feather.

5. Arachibutyrophobia
If you're extremely afraid of eating peanut butter in fear that it will stick to the roof of your mouth, you're probably arachibutyrophobic.

6. Plutophobia
If you give a plutophobic a winning lottery ticket...they'll run from you faster than you can say "cha-ching" It's not that they don't trust you, they're just completely terrified of wealth.

7. Octophobia
Don't take an octophobic to a figure skating competition, because one beautiful figure-eight and they're outta there faster than you can...count to eight.

8. Pteridophobia
What a nice potted fern you have on your porch! Unless you're pteridophobic, then you've probably hired someone to remove it right away. Ferns just give you the willies.

9. Cainophobia
Don't bring a present to a cainophobic's birthday party. It's not that they don't deserve anything new, they're just terrified of it.

and last, but not least...

6. Hippopotomonstrosesquipedaliophobia
If you're afraid of every phobia name on this entire list, especially this one, you might be a hippopotomonstrosesquipedalophobic, who seldom uses words longer than three syllables due to their complete fear of them.