The Collaborative International Dictionary of English v.0.48:

microcomputer \microcomputer\ n.
   A small computer based on a microprocessor; in practise, at
   any given time in the technology of computer development, a
   microcomputer will be one that is less powerful than a
   minicomputer.

   Syn: personal computer, PC.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

microcomputer
    n 1: a small digital computer based on a microprocessor and
         designed to be used by one person at a time [syn: personal
         computer, PC, microcomputer]

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

microcomputer

   A computer based on a microprocessor.

   Contrast with minicomputer, mainframe.

   (1995-02-07)