What does leak mean?
A leak is an opening or escaping substance, especially a fluid or gas, such as a leak in a pipe or a leak of oil. The word also describes the unauthorized or accidental disclosure of information, as in a leak of confidential documents or a scandal that leaked to the press. As a verb, leak can describe either physical escape or the act of revealing something that was meant to remain private. It is used in both formal and informal English and is especially common in news reporting, technology, engineering, and household maintenance. A leak is not necessarily a large failure: even a small opening can allow a substance to escape, while an information leak may expose only a limited detail yet have serious consequences. The related adjective leaky describes something prone to leaking, and leakage refers to the process or amount escaping.
An opening through which a fluid, gas, or other substance escapes, or an unauthorized or accidental disclosure of information.
"The engineers searched for a leak in the pipeline."
In journalism and everyday conversation, the information sense is common. In technical contexts, a leak usually refers to a physical escape of fluid or gas.
To escape through an opening or to become disclosed, especially without authorization.
"The report leaked before the official announcement was made."
The verb can be intransitive, as in 'the water leaked,' or transitive, especially in the information sense, as in 'an official leaked the findings.'
Use the plural when referring to multiple openings, instances of escape, or separate disclosures of information.
"Several leaks in the roof required immediate repair."
A leak can describe both a hole in a pipe and a secret escaping into the world.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does leak come from?
The word comes from Middle English, where it was used for both the act of escaping and an opening through which something escapes. Its development was influenced by related forms in other Germanic languages, including Dutch lekken and German lecken, which share the same broad verbal root. In modern English, the noun and verb have expanded from physical escape to include the disclosure of confidential or sensitive information.
Related word forms
How leak is actually used
The information sense is often used when something is disclosed accidentally, improperly, or without authorization. In technical and industrial contexts, leak commonly refers to a fluid or gas escaping from a container or system.
Easily confused with leak
A leak is the opening or act of escaping, whereas leakage is the amount or process of liquid or gas escaping.
A leak is a noun or verb, while leaky is an adjective describing something that permits leaks.