Also in this week's column:

• What makes a wound stop bleeding?
• Why are opera singers fat?
• Why don't humans molt?

Asked by Anka Saarinen of Helsinki, Finland

The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) of the American Psychiatric Association is the main diagnostic reference book for mental health professionals in the US and in much of the rest of the world.

According to the DSM-IV, a phobia is a persistent and irrational fear of a specific object, activity, or situation (the phobic stimulus) that results in a compelling desire to avoid it. This often leads either to avoidance of the phobic stimulus or to enduring it with dread.

A study by the National Institute of Mental Health in Bethesda, Maryland found that between 8.7 and 18.1 per cent of Americans suffer from at least one phobia. Yet for reasons unknown, the mental health profession cannot agree on the term to be used for many of the most common phobias. There are 11 names for the persistent and irrational fear of being dirty - Automysophobia, Coprophobia, Misophobia, Molysmophobia, Molysomophobia, Mysophobia, Rupophobia, Rypophobia, Scatophobia, Spermophobia, and Verminophobia.

There are eight names for the persistent and irrational fear of water - Aquaphobia, Caninophobia, Cynophobia, Hydrophobia, Hydrophobophobia, Kynophobia, Lyssophobia, and Nautophobia. There are seven names for the persistent and irrational fear of anything new - Cainophobia, Cainotophobia, Centophobia, Kainolophobia, Kainophobia, Kainotophobia, and Neophobi; being alone - Autophobia, Eremiophobia, Eremophobia, Ermitophibia, Isolophobia, and Monophobia; Odours - Autodysosmophobia, Automysophobia, Bromidrophobia, Bromidrosiphobia, Olfactophobia, Osmophobia, and Osphresiophobia; and pain -Agliophobia, Algophobia, Ergasiophobia, Ergophobia, Odynephobia, Odynophobia, and Ponophobia.

There are six names for the persistent and irrational fear of being touched - Aphenphosmphobia, Aphephobia, Chiraptophobia, Haphephobia, Haptephobia, and Haptophobia; cats - Aclurophobia, Ailurophobia, Elurophobia, Felinophobia, Galeophobia, and Gatophobia; cold - Cheimaphobia, Cheimatophobia, Cryophobia, Frigophobia, Pagophobia, and Psychrophobia; Heights - Acrophobia, Altophobia, Bathophobia, Batophobia, Hypsiphobia, and Hypsophobia; night - Achluophobia, Lygophobia, Myctophobia, Noctiphobia, Nyctophobia, and Scotophobia; red (colour or word) - Ereuthophobia, Ereuthrophobia, Erythrophobia, Erthyrophobia, Erytophobia, and Rhodophobia); thunder - Astraphobia, Astrapophobia, Brontophobia, Ceraunophobia, Keraunophobia, and Tonitrophobia; and walking - Ambulophobia, Basiphobia, Basophobia, Basostasophobia, Stasibasiphobia, and Stasiphobia.

Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au

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