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.

---

verb (used with object)

defensed, defensing

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

Other Word Forms

Derived Forms

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

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

Considered a prisoner of conscience by Amnesty International, Rivera was barred from seeing his family and denied the right to a defense during his detention.

From Barron's • Jun. 8, 2026

SpaceX is a much smaller government contractor than big defense companies like Lockheed Martin and Northrop Grumman.

From The Wall Street Journal • Jun. 8, 2026

The Fire defense smothered her, and while Erica Wheeler and Ogwumike made some shots early, the Sparks mostly didn’t make Portland pay for doubling up their star.

From Los Angeles Times • Jun. 8, 2026

Towns has always been an elite shooter, but not not ago, it was easy to find Knicks fans fed up with the big man’s ambivalent defense and virtuosity at collecting foolish fouls.

From The Wall Street Journal • Jun. 8, 2026

A new liberal government under Alexander Kerensky vowed to continue the war for the defense of the Russian homeland.

From "The War to End All Wars: World War I" by Russell Freedman