The One Standard German Axiom (OSGA) is a concept by Austrian-Canadian UBC linguist Stefan Dollinger from his 2019 monograph The Pluricentricity Debate. OSGA is used to describe the long-standing "scepticism" towards or "outright rejection" of the idea of multiple standard varieties in German dialectology and linguistics. It has been elaborated in several articles since and is the central theme in the 2025 general audience book Austrian German: a 300-year Love Story.