Yaw is one of three angles used to describe the orientation of an object in three-dimensional space. These angles are commonly referred to as Yaw, Pitch, and Roll.
Yaw: The angle that defines the rotation of an object about the vertical axis (Z axis). You can think of yaw as the angle of rotation that changes the horizontal orientation of an object, such as rotating about the vertical axis of an airplane to change its direction to the right or left.