- The angle at which an orbit is tilted to some given plane – in the solar system, usually that of the ecliptic. One of the elements of an orbit which define its size, shape and disposition in space.
- The angle produced by the deviation of a surface or line from the vertical or horizontal.
- The angle between a given plane and a reference plane. For instance, that between a geocentric orbit and the equator.
- For a given location on the surface of the earth, the angle between the horizontal plane and the direction of the lines of force of the earth's magnetic field. Inclination is 0° at the magnetic equator and 90° at each of the magnetic poles. Also called magnetic dip, magnetic inclination, or dip (3).
- The action of bending or tilting.
- A surface with a slant. Also, the slant itself.