Phobia

Psychologists use the term phobia, which comes from the Greek for fear, for a number of psychologic conditions that can seriously disable their carriers.

The name of a phobia contains a Greek word for what the patient fears plus -phobia; common phobias include these:

acrophobia, fear of heights
arachnophobia, fear of spiders
agoraphobia, fear of open places, from agora = public square
aleurophobia, fear of cats
claustrophobia, fear of small spaces

Psychiatrists often use virtual reality to desensitize patients to the feared thing.

In some cases, however, a fear or hatred is only based on ignorance; psychologists do not classify these as true phobias.

homophobia, fear of homosexual people
xenophobia, fear of strangers or the unknown