mightiness Meaning, Definition & Usage

  1. noun physical strength
    might; power.

WordNet

Might"i*ness noun
Definitions
  1. The quality of being mighty; possession of might; power; greatness; high dignity.
    How soon this mightiness meets misery. Shak.
  2. Highness; excellency; -- with a possessive pronoun, a title of dignity; as, their high mightinesses.

Webster 1913