Bavarian can either

• when used as an adjective, refer to the German state of Bavaria; or
• refer to the Bavarian or Austro-Bavarian language, a group of closely related dialects spoken in parts of Bavaria, most of Austria and the South Tyrol.

In German, the two usages are distinghuished ortographically, with bayrisch referring to the state and bairisch referring to the language.

Note to Wikipedia editors: It is recommended that links are set directly either to Bavaria or Austro-Bavarian in order to avoid confusion.