Triskaidekaphobia

Triskaidekaphobia is an intense or irrational fear of the number 13. It can lead people to avoid dates, addresses, or other situations associated with the number.

Friday the 13th: A calendar date considered unlucky in some Western cultures when the 13th day of a month falls on a Friday. It is the most familiar recurring setting in which fear of 13 becomes a shared cultural event.
Number 13 in buildings: The omission or altered labeling of the thirteenth floor in some buildings. Some building owners accommodate discomfort about 13 by labeling that floor 14 or another number.
Superstition: A belief or practice attributing events to supernatural or otherwise unsupported causal forces. Believing 13 is unlucky does not by itself establish an intense phobic response.
Classical conditioning: A learning process in which a previously neutral cue comes to trigger a response through association. It offers one account of how 13 might become linked with threat or distress.
Last Supper: The final meal Jesus shared with his disciples before his arrest and crucifixion, as described in the New Testament. A popular Christian tradition links the supper's thirteen diners with later suspicion of the number.
Numerical avoidance: The practice of avoiding particular numbers in names, dates, addresses, or other settings. It describes behaviors that may result when fear of 13 shapes ordinary decisions.
Anxiety disorder: A group of mental disorders characterized by excessive fear, anxiety, or related behavioral disturbance. Triskaidekaphobia becomes a clinical concern when its symptoms fit diagnostic standards and cause significant impairment.
Observational learning: Learning that occurs by watching other people’s behavior and its consequences. Seeing family or community members avoid 13 may help transmit the fear.
Unlucky number: A number believed by some people or cultures to bring bad luck. Triskaidekaphobia is a specific fear shaped by the broader idea that a number can carry ill fortune.
Avoidance coping: A coping strategy that reduces contact with situations associated with distress. Avoiding dates or places marked by 13 can provide short-term relief while maintaining the fear.

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HexakosioihexekontahexaphobiaRelated: It provides a parallel example of number-specific fear shaped by cultural beliefs.