z-lister

z-lister?
is this an opposite to a list?
then why not a lister?
why not z-list?
help plz
thanks

The "A list" is the compilation of celebrities and luminaries who attend the movie openings and lavish parties in Monaco. Jet setters. They are, therefore, A-listers.
Z-listers are, by extreme contrast, those slobs at the other end of the social spectrum. The scruffy guy who installed your cable. The bible-thumping mumbler on the subway platform. Me.