What is the actual definition of rotational motion?

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Rotational motion refers to the movement of an object around an axis, which can be fixed or not. The general case involves the axis of rotation translating or rotating relative to another reference point. An object in free motion does not necessarily rotate around a fixed axis, and its angular momentum remains constant unless acted upon by external torques. If the rotation is not about one of the object's principal axes, angular momentum and angular velocity will not align, causing the object to tumble. This nuanced understanding of rotational motion is essential for grasping its complexities in physics.
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Ok so I roughly know what rotational motion is (e.g. the spinning of a DVD) but I wish to know the textbook definition for it. I tried Googling it but to no avail. The first link on Google gives this:

Rotation around a fixed axis is a special case of rotational motion

http://en.wikipedia.org/wiki/Rotation_around_a_fixed_axis

But as mentioned above, that is a special case only, so what is a general case of rotational motion? IE is there a definition for it?

Thanks
 
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The general case is where the axis of rotation itself may be translating or rotating w.r.t. another reference.
 
A free object does not in general rotate about a fixed axis. The object's angular momentum will be constant if no external torques are exerted on the object, but even that does not mean that it will rotate about a fixed axis. Angular momentum and angular velocity will point in different directions if the instantaneous rotation is not about one of the object's principal axes. The object will tumble. Or, as Goldstein puts it in his text Classical Mechanics, "The polhode rolls without slipping on the herpolhode lying in the invariant plane."
 
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