The phrase "iron-hand" can be substituted with a variety of synonyms that convey a similar meaning of strong authority and control. Some examples include "firm grip", "rigid control", "unyielding authority", "forceful dominance" and "steely grip". Other alternatives include "strong rule", "domineering power", "resolute grasp" and "strict command". Each of these synonyms highlights the idea of a powerful and commanding leader who exerts their influence firmly and without hesitation. Whether it is in business, politics or personal relationships, there are many ways to describe someone who wields an iron-hand, and each one conveys a particular tone and emphasis.