Working point/working line
The working point -Bm, Hm- of a magnet is the intersection of the working line with the hysteresis curve
This establishes the strength and resistance to demagnetization of a magnet. For magnets with free poles and no external magnetic field, the angle between the working line and the B-axis is dependent on the magnet's length-to-diameter ratio.
Read more about the term hysteresis curve on this page.