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

MCGA
       Multi Color Graphics Adapter (IBM, PS/2)


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

Multi-Color Graphics Array
MCGA

    (MCGA) One of IBM's less popular
   hardware video display standards for use in the IBM PS/2.
   MCGA can display 80*25 text in monochrome, 40*25 text in 256
   colours or 320*200 pixel graphics in 256 colors.  It is now
   obsolete.

   (2011-03-20)