The Collaborative International Dictionary of English v.0.48:

Tron \Tron\, n.
   See 3d Trone, 2. [Obs. or Scot.]
   [1913 Webster]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

TRON
       The Realtime Operating system Nucleus


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

tron
 v.

    [NRL, CMU; prob. fr. the movie Tron] To become inaccessible except via
    email or talk(1), especially when one is normally available via telephone
    or in person. Frequently used in the past tense, as in: ?Ran seems to have
    tronned on us this week? or ?Gee, Ran, glad you were able to un-tron
    yourself?. One may also speak of tron mode; compare spod.

    Note that many dialects of BASIC have a TRON/TROFF command pair that
    enables/disables line number tracing; this has no obvious relationship to
    the slang usage.


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

TRON

   1.  The Real-Time Operating System Nucleus.

   2.  (TRace ON) A
   command used when debugging programs written in
   early line-numbered BASIC that contained GOTO and
   GOSUB statements.

   When the TRON command had been executed, the program ran
   with a window open indicating the line number being
   executed at that instant.

   The TROFF (an abbreviation for "TRace OFF") command turned
   the tracing off.

   (2003-02-02)


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

tron

    (NRL, CMU, probably from the film "Tron") To
   become inaccessible except via electronic mail or talk
   especially when one is normally available via telephone or in
   person.

   Compare spod.

   [Jargon File]

   (1994-11-03)