1 definition by Joefeather

The undergarment worn on the waist to thigh and pelvic region when running, either for exercise, sports, pursuit or evasion. This undergarment absorbs perspiration and holds the genitals intact. It should not be worn continually after running, and should be washed soon afterwards.
"When I finished jogging at the track today, my runderwear were soaking wet and quite pungent!"
by Joefeather May 16, 2013
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