leak

American  

[leek] / lik /

noun

1. an unintended hole, crack, or the like, through which liquid, gas, light, etc., enters or escapes.

   a leak in the roof.

2. an act or instance of leaking.

3. any means of unintended entrance or escape.

4. Electricity. the loss of current from a conductor, usually resulting from poor insulation.

5. a disclosure of secret, especially official, information, as to the news media, by an unnamed source.

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verb (used without object)

1. to let a liquid, gas, light, etc., enter or escape, as through an unintended hole or crack.

   The boat leaks.

2. to pass in or out in this manner, as liquid, gas, or light.

   gas leaking from a pipe.

3. to become known unintentionally (usually followed byout ).

   The news leaked out.

4. to disclose secret, especially official, information anonymously, as to the news media.

   The official revealed that he had leaked to the press in the hope of saving his own reputation.

verb (used with object)

1. to let (liquid, gas, light, etc.) enter or escape.

   This camera leaks light.

2. to allow to become known, as information given out covertly.

   to leak the news of the ambassador's visit.

idioms

1. take a leak, to urinate.

leak British  

/ liːk /

noun

1. 1. a crack, hole, etc, that allows the accidental escape or entrance of fluid, light, etc

   2. such escaping or entering fluid, light, etc

2. to develop a leak

3. something resembling this in effect

   a leak in the defence system

4. the loss of current from an electrical conductor because of faulty insulation, etc

5. a disclosure, often intentional, of secret information

6. the act or an instance of leaking

7. a slang word for urination See urination

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verb

1. to enter or escape or allow to enter or escape through a crack, hole, etc

2. to disclose (secret information), often intentionally, or (of secret information) to be disclosed

3. (intr) a slang word for urinate

Other Word Forms

• leaker
  noun
• leakless
  adjective
• nonleaking
  adjective

Etymology

Origin of leak

1375–1425; 1955–60 leak for def. 11; late Middle English leken < Old Norse leka to drip, leak; akin to Dutch lek, obsolete German lech leaky. See leach ¹

Explanation

A leak involves the release of something. It can be a behind-someone’s-back leak of sensitive information, a leak from a milk carton, or a leak in the roof that lets rain water drip in. As a verb, leak means to allow light or fluid to escape, or to enter or escape as though through a hole. Light can leak in through the curtains, water can leak out of an almost-closed faucet, or information can leak to the press. A leak is almost always a bad thing — it indicates that something that should be contained has broken out or escaped.

Example Sentences

The leak also depletes the source for a chemical reaction, which is generating heat that, in turn, accelerates the reaction in a process called “thermal runaway.”

From Los Angeles Times • May 24, 2026

There was no indication as to what caused the leak, which was initially reported on Thursday, and McGovern did not comment on whether the crack was linked to the leak.

From Barron's • May 24, 2026

The Birmingham, UK-headquartered company develops airplane technology and said in a statement Sunday that it is "working around the clock to mitigate the risk of a leak."

From Barron's • May 24, 2026

California authorities were bracing Saturday for a leak or explosion that could send toxic vapors into the air after efforts to contain a damaged chemical tank made little headway.

From The Wall Street Journal • May 23, 2026

The Human was confused and disappointed, and it seemed that his eyes might leak again.

From "Klawde: Evil Alien Warlord Cat" by Johnny Marciano and Emily Chenoweth

Related Words

• discharge
• disclose
• divulge
• escape
• ooze
• pass on
• reveal
• spill
• trickle