strict or harsh control: The general governed the country with an iron hand.
Origin of iron hand
First recorded in 1840–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
harsh or rigorous control; overbearing or autocratic forcehe ruled with an iron hand
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Rigorous control, as in He ruled the company with an iron hand. This usage is sometimes put as iron hand in a velvet glove, meaning “firm but seemingly gentle control,” as in She runs the town with an iron hand in a velvet glove. [c. 1700]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.