Gymnophobics experience anxiety from nudity, even if they realize their fear is irrational. They may worry about seeing others naked, being seen naked, or both. Their fear may stem from a general anxiety about sexuality, from a fear that they are physically inferior, or from a fear that their nakedness leaves them exposed and unprotected.

Gymnophobics often attempt to rationalize the condition by avoidance or shunning of many forms of nudity, or such as using modesty or other seemingly rational or moral grounds. Many people avoid public nudity as well as nudity in private situations, and some have an aversion to nudity as an aspect of prudishness or body shame.

The term gymnophobia comes from the Greek γυμνός - gumnos, "naked" and φόβος - phobos, "fear". A phobia that has a significant amount of overlap with gymnophobia is dishabiliophobia, which is the fear of undressing in front of others.

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