A Chicago strip club just got schooled on how to spell L-O-S-E-R ... because a judge has ruled it can't use the name "Magic City" -- or any version ... no matter how it's spelled.
TMZ broke the story ... Atlanta's infamous "Magic City" strip club sued the Chicago joint for trying to jack the club's name that has become iconic in the rap world -- with regulars like Jay Z, Ludacris and Outkast.
A judge just ruled the ATL club has cornered the market on the name, ordering the Chi-town club to stop using the name Magic or any variation, including Majik, Majic, and Magik.
The Chicago owners are required to take out ads apologizing for confusing customers.
Ass-clapping ATL strip clubs ... accept no substitutions.