Fear of loneliness: An abnormal and persistent fear of loneliness, of being alone. Sufferers of this fear experience undue anxiety even though they realize that being alone does not threaten their well-being. They may worry about being ignored and unloved, or they may worry about intruders, strange noises or the possibility of developing a medical problem.
Fear of loneliness is termed "autophobia," a word derived from two Greek words: "autos" (self) and "phobos" (fear). "Autos" has given us many English words such as "automatic" and "automotive" (self-moving) and "autonomy" (self-governing). And "phobos" has bequeathed us a vast number of phobias such as "claustrophobia" (fear of closed places) and "acrophobia" (fear of heights).