@Tim H A lot of the code I work with originated on Alpha Microsystems hardware in a dialect of basic where variable names were limited to 6 characters. Tokens were Rad-50 encoded, which would fit 6 characters into 2 16-bit words. That was the limitation. We still have a lot of those variable names floating around our "modern" code.
I once had to work ( a long time ago ) debugging a fairly big COBOL program written by an ex-assembler programmer who had named his WORKING-STORAGE fields after the Z80 registers and used these fields ( some type-redefined ) for anything and everything throughout the code.