defense

American  

[dih-fens, dee-fens] / dɪˈfɛns, ˈdi fɛns /

noun

1. resistance against attack; protection.

   Two more regiments are needed for the defense of the city.

   Synonyms:

   safeguard, security

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.

3. the support of a cause or the like by speech, argument, etc..

   He spoke in defense of the nation's foreign policy.

   Synonyms:

   justification, advocacy, support

4. a speech, argument, etc., in vindication.

   She delivered a defense of free enterprise.

5. Law.

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

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

   3. a defendant and their counsel.

6. Psychology. defense mechanism.

7. Sports.

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

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

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

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

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

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verb (used with object)

defensed, defensing

1. Sports. to defend against (an opponent, play, or tactic).

Other Word Forms

• defenseless
  adjective
• defenselessly
  adverb
• defenselessness
  noun
• nondefense
  noun
• predefense
  noun
• undefensed
  adjective

Etymology

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

Explanation

Defense has to do with protecting something or fighting against an opponent, whether it's national defense, a football team's defense, or a defense lawyer. Defense is the opposite of offense. It has to do with defending against all sorts of things: In the military, defense is about protecting a country from attack. In sports, defense is supposed to stop the other team from scoring. A defense attorney tries to prove his client is innocent. A defense can even be an excuse for doing something, as in "In my own defense, I was sleepwalking at the time."

Example Sentences

“The threat posed by drones is highly digital. This is why effective defense requires a combination of sensors, effectors, and secure communication networks,” Rheinmetall Chief Executive Armin Papperger said.

From The Wall Street Journal • May 11, 2026

That’s not even one-millionth of 1 percent of the $540 billion in defense spending.

From Slate • May 11, 2026

But mostly, the Sparks’ defense activated, forcing 10 turnovers, led by two steals apiece from Ariel Atkins and Erica Wheeler to fuel the comeback.

From Los Angeles Times • May 10, 2026

Powell’s calm but forceful defense of Fed independence likely staved off larger attacks on the institution and won him admiration and awards, like the John F. Kennedy Profile in Courage award.

From MarketWatch • May 10, 2026

"I know what fear is," Dasch wrote in his defense.

From Nazi Saboteurs by Samantha Seiple