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

gonk
 /gonk/, vi.,n.

    1. [prob. back-formed from gonkulator.] To prevaricate or to embellish
    the truth beyond any reasonable recognition. In German the term is
    (mythically) gonken; in Spanish the verb becomes gonkar. ?You're gonking
    me. That story you just told me is a bunch of gonk.? In German, for
    example, ?Du gonkst mich? (You're pulling my leg). See also gonkulator.

    2. [British] To grab some sleep at an odd time; compare gronk out.


The Free On-line Dictionary of Computing (30 December 2018):

gonk

    /gonk/ 1. To prevaricate or to embellish the truth
   beyond any reasonable recognition.  In German the term is
   (mythically) "gonken"; in Spanish the verb becomes "gonkar".
   "You're gonking me.  That story you just told me is a bunch of
   gonk."  In German, for example, "Du gonkst mir" (You're
   pulling my leg).

   See also gonkulator.

   2. (British) To grab some sleep at an odd time.

   Compare gronk out.

   [Jargon File]

   (1995-03-07)