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Synonyms

defense

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

noun

  • defenses
    plural
  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

Inflected Forms

Nouns

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."

Keep Reading on Vocabulary.com

Vocabulary lists containing defense

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

As they say, the best defense is a good offense.

From Salon Aug. 17, 2026

Lula has vowed to increase defense spending, and to prioritize the fight against organized crime.

From Barron's Aug. 16, 2026

Reiner’s former defense lawyer, Alan Jackson, quit the case in January.

From Los Angeles Times Aug. 16, 2026

GM has been more eager to branch off into defense work, while Ford has pared down its small-car lineup to double down on its most profitable “iconic” vehicles.

From The Wall Street Journal Aug. 15, 2026

But in my defense, it had seemed like a good idea at the time—a way to include her in something important to me.

From "Bye Forever, I Guess" by Jodi Meadows

The US stations about 28,500 troops in South Korea to bolster the country's defenses against military threats from Pyongyang.

From Barron's Aug. 16, 2026

For decades, scientists have generally viewed the brain's immune system as largely separate from the immune defenses operating throughout the rest of the body.

From Science Daily Aug. 14, 2026

The plane swap prompted renewed scrutiny of the Qatar-gifted jet, which the Times reported did not have the same security features as the older jet, including anti-missile defenses.

From Barron's Aug. 11, 2026

Stores of critical air defenses are also low, including Patriot, SM-3 and Terminal High Altitude Area Defense interceptors, as well as Thaad radars and air defense artillery units, the officials added.

From The Wall Street Journal Aug. 7, 2026

He examined her face, saw that she looked at him without her usual defenses.

From "Anger Is a Gift" by Mark Oshiro

Over his career, he has 253 tackles and 17 passes defensed.

From Los Angeles Times Oct. 27, 2025

Gilman started all five games for the Chargers this season with 22 tackles and three passes defensed.

From Los Angeles Times Oct. 7, 2025

In his first start of the season, Burns responded with five tackles and one pass defensed in 63 snaps.

From Seattle Times Dec. 21, 2023

Jordyn Brooks was all over the field, generating nine tackles, two for loss, half a sack and a pass defensed.

From Seattle Times Oct. 23, 2023

Then I may think myself to be Well recompensed, For wearing of the tree that is So well defensed Against all weather that doth fall When wayward winter spits his gall.

From A History of Elizabethan Literature by George Saintsbury

It's also impossible not to look at the fact we could of and should have done a better job of defensing it.

From Seattle Times Dec. 8, 2011

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