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.

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verb (used with object)

defensed, defensing

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

Other Word Forms

Derived Forms

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

Inflected Forms

Nouns

• defenses
  plural

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

See Examples For:

defense defenses defensed defensing

Inflammation is one of the immune system's most important defense responses.

From Science Daily ● Sep. 13, 2026

Researchers also found substantial overlap between genes associated with aging and genes involved in disease defense, suggesting that studying one process could help explain the other.

From Science Daily ● Sep. 12, 2026

The additions of All-Pro cornerback Trent McDuffie, record-setting edge rusher Myles Garrett and cornerback Jaylen Watson were supposed to supercharge the Rams’ defense.

From Los Angeles Times ● Sep. 11, 2026

Venture-capital firm Andreessen Horowitz is opening a new regional headquarters in West Palm Beach, focusing on defense and national security startups through its $1.18 billion American Dynamism fund.

From The Wall Street Journal ● Sep. 10, 2026

“You might like defense more once you get used to it. Or maybe after a while you’ll get to switch positions.”

From "Keeping Pace" by Laurie Morrison

Researchers have identified a promising way to weaken one of pancreatic cancer's key defenses against treatment.

From Science Daily ● Sep. 12, 2026

We began working through basic hapkido hand techniques, defenses designed to control an attacker through redirection of force.

From Los Angeles Times ● Sep. 11, 2026

You can see something similar in the body politic, when the sudden appearance of something new and confusing kicks societal defenses into overdrive.

From Salon ● Sep. 11, 2026

Canada offered support Thursday to boost Ukraine's air defenses and help replenish its drone stocks, as the countries pledged to deepen their alliance during a visit by President Volodymyr Zelensky.

From Barron's ● Sep. 10, 2026

I put up the defenses and shells that my brother taught me—there are eyes everywhere online.

From "Legend" by Marie Lu

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

From Los Angeles Times ● Oct. 7, 2025

This is his sixth season, all with the Chargers, and for his career has five interceptions and 21 passes defensed.

From Los Angeles Times ● Oct. 7, 2025

Sneed had two interceptions and 14 passes defensed in 16 games last season, giving him 10 interceptions and 40 passes defensed in his four-year career.

From Seattle Times ● Mar. 22, 2024

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