Grundneigung

Grundneigung is a German term used in several technical fields to denote the base or principal inclination of a line, surface or object relative to a reference direction or plane. The exact meaning varies by discipline and is not a standardized English term, but it generally refers to the baseline tilt from which other angles are measured.

In mathematics and analytic geometry, the Grundneigung of a line in a plane is the angle between the line and a fixed reference line, commonly the horizontal or Grundlinie. It determines the slope of the line: if the line has slope m, the Grundneigung equals arctan(m).

In geology and geomorphology, Grundneigung may describe the base tilt of a surface or layer, such as the inclination of a bed or the overall slope of a hillside, usually given in degrees from the horizontal. It is related to, but not identical with, terms such as dip and strike.

In surveying, civil engineering and architecture, Grundneigung can denote the foundational tilt used when modeling loads, drainage or earthworks; the term is context-dependent and often replaced by more precise terms such as Gefälle (gradient) or Neigung (inclination).

See also Neigung, Hangneigung, Dip, Inklination, Gefälle. Due to its field-specific usage, Grundneigung should be interpreted in light of the particular discipline and accompanying definitions in the relevant texts.