I do think, the term eigenvalue is rather opaque, and should be replaced by a more plain-english terminology that readily conveys its meaning.
Perhaps, we should compromise and name it after Leonhard Euler? That should clear up the confusion.
Scale of aspect?
Aspect factor?
Scale along Axis?
Axial scaling factor?
Natural scaling?
Propensity?
Leaning factor?
In geography for example(quoting from Wikipedia):
"In physical geography and physical geology, aspect (also known as exposure) is the compass direction or azimuth that a terrain surface faces."