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]

The Collaborative International Dictionary of English v.0.48:

jock \jock\ n.
   1. a person trained to compete in sports; an athlete.
      [WordNet sense 1]

   Syn: athlete.
        [WordNet 1.5]

   2. A jockstrap.
      [PJC]

   3. A disk jockey.
      [PJC]

   shock jock a radio talk-show host who is notorious for
      voicing unpopular, controversial, or shocking opinions
      guaranteed to offend many people.
      [PJC]

WordNet (r) 3.0 (2006):

jock
    n 1: a person trained to compete in sports [syn: athlete,
         jock]
    2: a support for the genitals worn by men engaging in strenuous
       exercise [syn: athletic supporter, supporter,
       suspensor, jockstrap, jock]

The Free On-line Dictionary of Computing (19 January 2023):

jock
systems jock

   1. A programmer who is characterised by large and somewhat
   brute-force programs.

   2. When modified by another noun, describes a specialist in
   some particular computing area.  The compounds "compiler jock"
   and "systems jock" seem to be the best-established examples.

   [Jargon File]

   (1995-01-19)


The Jargon File (version 4.4.7, 29 Dec 2003):

jock
 n.

    1. A programmer who is characterized by large and somewhat brute-force
    programs. See brute force.

    2. When modified by another noun, describes a specialist in some particular
    computing area. The compounds compiler jock and systems jock seem to be the
    best-established examples.