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

OCODE

   An assembly language for a stack-based virtual machine,
   used as the intermediate language of the Cambridge BCPL
   compiler.

   ["The Portability of the BCPL Compiler", M. Richards, Soft
   Prac & Exp 1(2) (1971)].

   (1995-01-30)