The best mathematical fit to the observed geomagnetic field using a single dipole. If not stated, this is usually the geocentric dipole field, which is axial and inclined at about 11.3° relative to the Earth’s axis of rotation. The axial geocentric dipole field is the best-fitting dipole, located at the centre of the Earth and aligned along the Earth’s axis of rotation, and is usually considered to represent the Earth’s magnetic field after averaging out the geomagnetic secular variation. See also non-dipole field.