A fetish can be defined as an attraction to an inanimate object, or to a non-sexual part of the body, that arouses feelings in an individual. 

A fetish is also when an individual is sexually aroused by an object or objects to achieve sexual satisfaction.  Without that object being present, they may not achieve arousal.

The most common fetishes are PVC, rubber/latex and leather, but if there is an element of arousal or erotic feeling present, anything can become a fetish, it's very individual from person to person.   For example, some people have a fetish for boots or feet.

Many people in the BDSM community enjoy wearing 'Fetish' clothing without having a strictly fetishistic attraction to it.   It has been said it can enhance their need for Dominance or submission, but for others it may just be a way to express themselves, or that they may consider it an accepted way of dressing, in a sense, a bit like a uniform.