decalage

The difference in angle of incidence between the main wing and horizontal stabilizer, or between the canard and main wing, of an airplane.

The difference in angle of incidence of the two wings of a biplane.

The angle between two geometric lines that define an aerofoil.

In Piagetian developmental psychology, the inability to apply a learned function across all problems (horizontal decalage) or across different developmental stages (vertical decalage).