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}.

[glossary]