Rotation

The spin of a body on its axis.

Day

The time required for Earth to rotate once on its axis.

Revolution

The motion of a body that travels around another body in space; one complete trip along an orbit.

Year

The time required for Earth to orbit around the sun.

Season

A division of the year that is characterized by recurring weather conditions and determined by both Earth's tilt relative to the sun and Earth's position in its orbit around the sun.

Equinox

The movement when the sun appears to cross the celestial equator.

Solstice

The point at which the sun is as far north or as far south of the equator as possible.