Angular momentum
An object that is very spread-out from the axis of rotation has a large moment of inertia—it is very hard to make it start spinning, but once it gets going, it is very hard to make it stop. Similarly, it is easier to make an object start spinning at a low angular velocity than to make it start spinning at a high angular velocity. This is why the spin angular momentum depends both on how spread-out the object is (moment of inertia) and how fast it is spinning (angular velocity).