You're right, I searched wrong in my 386 manual. So apparently they did call it virtual addressing. I'm still not sure if I like calling that an "MMU". To me,

You're right, I searched wrong in my 386 manual. So apparently they did call it virtual addressing. I'm still not sure if I like calling that an "MMU". To me, an MMU acts on every memory access. But at the end of the day, who cares what I think what words mean. :) The critical distinction to me is that segmentation is not much more than, effectively, an indexed addressing mode, where the base is the segment base that has been loaded into the descriptor cache when the segment register was loaded. Nothing happens at the time of actually accessing memory, except for the limit check.