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

TCB
       Trusted Computing Base (MS, Palladium)


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

TCB
       Task Control Block (BS2000)


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

TCB
 /T?C?B/, n.

    [IBM] 1. Trouble Came Back. An intermittent or difficult-to-reproduce
    problem that has failed to respond to neglect or shotgun debugging.
    Compare heisenbug. Not to be confused with:

    2. Trusted Computing Base, an ?official? jargon term from the Orange Book
    .


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

TCB

   1.  Trouble Came Back.

   2.  (Orange Book) Trusted Computing Base.

   3.  Task Control Block.

   [Jargon File]

   (1998-07-02)