The name came from the feeling of speed and movement that angular curves have.
Race tracks are examples of this. Oval circuits allow high speeds thanks to the slope of the tracks that keep the cars on the ground. This centrifugal effect is what made it called Avus.
Avus was a very old circuit in Germany that was very innovative, it had a slope of more than 40º in the main curve. This track is full of history and, after a while, it became an urban road in Berlin, in addition to being considered the first motorway in Europe.