1. [n]  unauthorized (especially deliberate) disclosure of confidential information
2. [n]  the unwanted discharge of a fluid from some container; "they tried to stop the escape of gas from the damaged pipe"; "he had to clean up the leak"
3. [n]  an accidental hole that allows something (fluid or light etc.) to enter or escape; "one of the tires developed a leak"
4. [n]  a euphemism for urination; "he had to take a leak"
5. [n]  soft watery rot in fruits and vegetables caused by fungi
6. [v]  have an opening that allows light or substances to enter or go out; "The container leaks"
7. [v]  enter or escape as through a hole or crack or fissure; "Water leaked out of the can into the backpack"
8. [v]  be leaked; "The news leaked out despite his secrecy"
9. [v]  tell anonymously; "The news were leaked to the paper"

1. \Leak\, n. [Akin to D. lek leaky, a leak, G. leck, Icel.
   lekr leaky, Dan. l[ae]k leaky, a leak, Sw. l["a]ck; cf. AS.
   hlec full of cracks or leaky. Cf. {Leak}, v.]
   1. A crack, crevice, fissure, or hole which admits water or
      other fluid, or lets it escape; as, a leak in a roof; a
      leak in a boat; a leak in a gas pipe. ``One leak will sink
      a ship.'' --Bunyan.
   
   2. The entrance or escape of a fluid through a crack,
      fissure, or other aperture; as, the leak gained on the
      ship's pumps.
   
   {To spring a leak}, to open or crack so as to let in water;
      to begin to let in water; as, the ship sprung a leak.
   
   

2. \Leak\, a.
   Leaky. [Obs.] --Spenser.
   
   

3. \Leak\, v. i. [imp. & p. p. {Leaked}; p. pr. & vb. n.
   {Leaking}.] [Akin to D. lekken, G. lecken, lechen, Icel.
   leka, Dan. l[ae]kke, Sw. l["a]cka, AS. leccan to wet,
   moisten. See {Leak}, n.]
   1. To let water or other fluid in or out through a hole,
      crevice, etc.; as, the cask leaks; the roof leaks; the
      boat leaks.
   
   2. To enter or escape, as a fluid, through a hole, crevice,
      etc.; to pass gradually into, or out of, something; --
      usually with in or out.
   
   {To leak out}, to be divulged gradually or clandestinely; to
      become public; as, the facts leaked out.
   
   

4. \Leak\, n. (Elec.)
   A loss of electricity through imperfect insulation; also, the
   point at which such loss occurs.
   
   

With a qualifier, one of a class of resource-management bugs that occur when resources are not freed properly after operations on them are finished, so they effectively disappear (leak out). This leads to eventual exhaustion as new allocation requests come in.

One might refer to, say, a "window handle leak" in a window system.

See memory leak, fd leak.

[jargon file]