verb (used with object)
to make pitiless or unfeeling: to harden one's heart.
to make rigid or unyielding; stiffen: The rigors of poverty hardened his personality.
to strengthen or confirm, especially with reference to character, intentions, feelings, etc.; reinforce.
to make hardy, robust, or capable of endurance; toughen.
Military. to reinforce the structure of (a military or strategic installation) to protect it from nuclear bombardment.
verb (used without object)
to become hard or harder.
to become pitiless or unfeeling.
to become rigid or unyielding; stiffen: His personality hardened over the years.
to become confirmed or strengthened: His resistance hardened.
to become inured or toughened: The troops hardened under constant fire.
12. Commerce. a.
to cease to fluctuate; firm: When the speculators withdrew from the market, the prices hardened.
Origin: 1150–1200; Middle English; Related forms
preharden, verb (used with object)
unharden, verb (used with object)
1. solidify, indurate; petrify, ossify. 4. fortify, steel, brace, nerve.
1. soften. 4. weaken.