Do you have a phobia? A phobia is described as "an extreme or irrational fear or aversion to something", and having a phobia about something is by no means uncommon.
For example, how many of us are scared of spiders? In some people the mere sight of a spider can trigger a near hysterical reaction, screaming and wanting to run away. In the UK at least, where spiders which can actually harm you are extremely rare, that response could seem irrational and difficult to understand.
Yet this fear of spiders is one of the most common phobias – arachnophobia. Other relatively common phobias include the fear of heights (acrophobia), the fear of confined spaces (claustrophobia), the fear of dogs (cynophobia), the fear of injections (trypanophobia) and the fear of flying (pteromerhanophobia).
You could argue there's nothing irrational about these fears; after all, dogs might bite, aeroplanes might crash and who would be enthusiastic about having needles stuck into them. It could also be that some of these fears are pre-programmed into us, part of a primeval survival instinct that most people simply overcome better than others. In some cases a phobia might have been brought on by a specific incident or trauma, or it might just develop gradually over time.
But it is the level of fear associated with these things that makes them irrational and marks them out as a phobia. It's one thing to be wary of a strange dog, quite another to be terrified of all dogs to the point of inducing severe anxiety and even hysteria.
So it's likely that many of us will have a phobia about something, even if only a mild one. However, there are also some very strange fears out there which are surprisingly common – so much so that they have been officially classified as a phobia. Here are 10 phobias which, while you might never understand them, are all too real to those who have them!
1. Turophobia... the fear of cheese. A surprising number of people are really scared of cheese, whether it's the sight of it, the smell, the feel or the taste. For some turophobes it is just one type of cheese, while for others any cheese could bring on a cold sweat.
2. Coulrophobia... the fear of clowns. Stephen King's film "It" has a lot to answer for! The scary clown has been found in popular culture for generations, and for some people any clown is scary. Some sufferers will not even venture into MacDonald's in case clown mascot Ronald MacDonald raises his painted head.
3. Nomophobia... fear of being without mobile phone coverage. Now here's a modern phobia that our ancestors need never have feared. Its name (short for no-mobile-phobia) was only coined less than a decade ago, but a growing number of sufferers exhibit an extreme fear of losing signal, running out of battery or even losing sight of their mobile phone.
4. Xanthophobia... fear of the colour yellow. Anything yellow, even the sun, can trigger anxiety in people with this phobia. Even the word "yellow" can bring on a reaction. Be careful who you give daffodils to!
5. Triskaidekaphobia... fear of the number 13. What starts out as a quaint superstition can bloom into a fully fledged terror of the number 13 in some people. It is often associated with fear of Friday the 13th, when some sufferers simply refuse to emerge from under the duvet. Others just avoid anything related to the "unlucky" number.
6. Pogonophobia... fear of beards. Facial hair has made a comeback in recent years, with "hipsters" sporting full bushy beards, but for some people it is the stuff of nightmares. Some psychologists suggest it is because it is hard to read the facial expressions of a man with a beard, and thereby fathom his intent. Or it could just be an inherited fear of Vikings.
7. Papaphobia... fear of the Pope. Being a practising Catholic could be a tough one if you're afflicted with this phobia. Seen as a branch of hierophobia (fear of holy individuals and sacred things), it can be triggered by a trauma associated with the Pope or the papacy.
8. Omphalophobia... fear of the naval. Just seeing or thinking about a belly button can repulse people with this phobia. It also extends to touching another person's naval or having their own naval touched or seen.
9. Somniphobia... fear of falling asleep. Repeated nightmares or worrying that you might die while asleep can result in an extreme fear of 'the land of nod'. Others just worry that too much of their precious time is wasted on sleep when there's so much else to do. The inevitability of falling asleep only makes the fear worse.
10. Gephyrophobia... the fear of crossing bridges. People with this phobia will go to extreme lengths to avoid crossing a bridge. Journeys have to be meticulously planned, often involving long diversions, or avoided altogether. Some sufferers only fear driving across a bridge, a fear so real that in certain American cities you can pay someone else to drive your car across a bridge.
Finally there is one more phobia to mention; phobophobia is the fear of phobias, and specifically of the feelings of anxiety and distress associated with them. Honestly, it exists.