Astronomy Answers: From the Astronomical Dictionary

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The description of the word you requested from the astronomical dictionary is given below.

the inclination

inclinatio = [Latin] slope

In astronomy, inclination is an angle between some direction and a standard plane. Inclination is used as name for

1. the angle between the orbit of a planet or other celestial body and the base plane of the coordinate system (usually the ecliptic for bodies in the Solar System). The inclination is one of the orbital elements.
2. the angle that the magnetic field makes with the local surface.