I'm studying the ILS or LOC RWY 3 approach chart for KMKC. I'm trying to figure out what "(CMFCC)" at the runway means.
Is it a computer navigation aid?
A point shown in parentheses like this is called a Computer Navigation Fix (CNF). If it didn't fall right at the end of the runway, it would be marked with a small X. It's defined in the legend on page 39 (page 41 of the PDF) of the Terminal Procedure Publication User's Guide.
These points are only used to define the navigation track in the flight computer. They should not be used by ATC, but pilots could use them for reference if their FMC or GPS shows them. There is a short AOPA article about them, arguing they should be removed from the charts. Here is a much longer PDF that has a bit more detail on their purpose and a lot more detail about making sure their usage and distinction are clear.