[ dih-fens or, especially for 7, 9, dee-fens ]
See synonyms for defense on
  1. resistance against attack; protection: Two more regiments are needed for the defense of the city.

  2. something that guards against harm, such as a fortification, physical or mental quality, or medication: This fort was once the main defense of the island.

  1. the support of a cause or the like by speech, argument, etc.: He spoke in defense of the nation's foreign policy.

  2. a speech, argument, etc., in vindication: She delivered a defense of free enterprise.

  3. Law.

    • the denial or pleading of the defendant in answer to the claim or charge that has been made.

    • the proceedings adopted by a defendant or the defendant's legal agents, for defending against the charges that have been made.

    • a defendant and their counsel.

  4. Sports.

    • the practice or art of shielding oneself or one's goal from attack, as in fencing, boxing, soccer, or football.

    • the team attempting to thwart the attack of the team having the ball or puck.

    • the players of a team who line up in their own defensive zone.

    • the positions on the field, ice, etc., taken by such players.

  5. (initial capital letter)Also called Defense Department. Informal. the Department of Defense.

verb (used with object),de·fensed, de·fens·ing.
  1. Sports. to defend against (an opponent, play, or tactic).

Origin of defense

First recorded in 1250–1300; Middle English from Old French from Late Latin dēfēnsa “a forbidding,” noun use of feminine of past participle of Latin dēfendere “to defend ”; replacing Middle English defens, from Anglo-French, Old French, from Medieval Latin defēnsum “(thing) forbidden,” neuter past participle of Latin dēfendere

Other words for defense

Other words from defense

  • de·fense·less, adjective
  • de·fense·less·ly, adverb
  • de·fense·less·ness, noun
  • non·de·fense, noun, adjective
  • pre·de·fense, noun
  • un·de·fensed, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use defense in a sentence

  • If we stayed where we were, our dead would kill us; if we moved out of our defenses, we should no longer be invincible.

  • At Norfolk nothing had been done but to strengthen the defenses.

  • In practice it was simple and, like most defenses, only partially effective.

    The Fire People | Ray Cummings
  • Then was heard an angry buzz, as the assaulted bees swarmed out of their defenses and literally stormed her.

  • Right after graduation, he was made second lieutenant of Engineers and for some time he was busy looking after our coast defenses.

    Robert E. Lee | Ruth Hill