jockstrap

from WordNet (r) 3.0 (2006)

jockstrap
    n 1: a support for the genitals worn by men engaging in
         strenuous exercise [syn: {athletic supporter}, {supporter},
         {suspensor}, {jockstrap}, {jock}]

from The Collaborative International Dictionary of English v.0.48

jockstrap \jock"strap`\ (j[o^]k"str[a^]p), n.
   1. A supporting undergarment for the external genitals worn
      by men engaging in vigorous athletic sports or strenuous
      exercise; called also {athletic supporter} and {jock}.

   Syn: jock; athletic supporter.
        [WordNet 1.5]