Thank you for your question!
An irrational fear of being watched or spied upon is not a phobia per
se, but a form of paranoia. Dictionary.com defines paranoia as the
1. A psychotic disorder characterized by delusions of persecution with
or without grandeur, often strenuously defended with apparent logic
2. Extreme, irrational distrust of others
Paranoia occurs in varying degrees. It can be acute and no cause for
great alarm, occuring when a person is depressed, placed under severe
stress or faced with a new situation (e.g. a new job). Acute paranoias
can also be triggered by drug and alcohol use and even PMS; they
generally last no longer than a couple of months. However, paranoia
can also be a symptom of clinical disorders like schizophrenia,
delusional paranoid disorder (persecutory paranoid disorder) or the
less serious paranoid personality disorder (persons with paranoid
personality disorder do not lose touch with reality).
A suspicion that is grossly exaggerated and unfounded is referred to
as a "delusion." An article at BluePrint for Health
(http://blueprint.bluecrossmn.com/topic/topic100587259) offers this
description of delusions:
"Delusions are firmly held beliefs that are untrue, not shared by
others in the culture, and not easily modifiable. The most common
delusion in delusional disorder is that of persecution. While persons
with paranoid personality might suspect their colleagues of joking at
their expense, persons with delusional disorder may suspect others of
participating in elaborate master plots to persecute them. They
believe that they are being poisoned, drugged, spied upon, or are the
targets of conspiracies to ruin their reputations or even to kill
them. They sometimes engage in litigation in an attempt to redress
The suspicion you describe, if completely unfounded in reality (i.e.
the person has not been previously stalked or spied upon), would
qualify as a delusion. If you or someone you know is experiencing this
"fear of being watched" to a degree that you feel is cause for alarm,
please consult a medical professional; Google Answers is not qualified
to provide diagnoses or comprehensive medical advice.
In closing, it should also be noted that such suspicions, within
reason, might not be so uncommon; the current "war on terror" has
caused many to be more alert to potential privacy invasions,
governmental or otherwise.
For more information:
Useful information on...paranoia
Definition of paranoia
I used the following search strings to find your answer:
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phobia being watched spied on
All the best!