Definition of tyranny



  1. 1:  oppressive powerevery form of tyranny over the mind of man — Thomas Jefferson; especially :  oppressive power exerted by governmentthe tyranny of a police state

  2. 2a :  a government in which absolute power is vested in a single ruler; especially :  one characteristic of an ancient Greek city-stateb :  the office, authority, and administration of a tyrant

  3. 3:  a rigorous condition imposed by some outside agency or forceliving under the tyranny of the clock — Dixon Wecter

  4. 4:  an oppressive, harsh, or unjust act :  a tyrannical act workers who had sufferedtyrannies