patch
     n 1: a small contrasting part of something; "a bald spot"; "a
          leopard's spots"; "a patch of clouds"; "patches of thin
          ice"; "a fleck of red" [syn: {spot}, {speckle}, {dapple},
           {fleck}, {maculation}]
     2: a small area of ground covered by specific vegetation; "a
        bean plot"; "a cabbage patch"; "a briar patch" [syn: {plot},
         {plot of ground}]
     3: a piece of cloth used as decoration or to mend or cover a
        hole
     4: a period of indeterminate length (usually short) marked by
        some action or condition; "he was here for a little
        while"; "I need to rest for a piece"; "a spell of good
        weather"; "a patch of bad weather" [syn: {while}, {piece},
         {spell}]
     5: a short set of commands to correct a bug in a computer
        program
     6: a connection intended to be used for a limited time [syn: {temporary
        hookup}]
     7: sewing or darning that repairs a worn or torn hole
        (especially in a garment); "her stockings had several
        mends" [syn: {mend}, {darn}]
     8: a protective cloth covering for an injured eye [syn: {eyepatch}]
     9: a piece of soft material that covers and protects an injured
        part of the body [syn: {bandage}]
     v 1: to join or unite the pieces of; "patch the skirt" [syn: {piece}]
     2: provide with a patch; also used metaphorically; "The field
        was patched with snow"
     3: mend by putting a patch on; "patch a hole" [syn: {patch up}]
     4: repair by adding pieces; "She pieced the china cup" [syn: {piece}]
Source: WordNet® 2.0

patch 1. n. A temporary addition to a piece of code, usually as a
   {quick-and-dirty} remedy to an existing bug or misfeature. A patch may
   or may not work, and may or may not eventually be incorporated
   permanently into the program. Distinguished from a {diff} or {mod} by
   the fact that a patch is generated by more primitive means than the rest
   of the program; the classical examples are instructions modified by
   using the front panel switches, and changes made directly to the binary
   executable of a program originally written in an {HLL}. Compare
   {one-line fix}. 2. vt. To insert a patch into a piece of code. 3. [in
   the Unix world] n. A {diff} (sense 2). 4. A set of modifications to
   binaries to be applied by a patching program. IBM operating systems
   often receive updates to the operating system in the form of absolute
   hexadecimal patches. If you have modified your OS, you have to
   disassemble these back to the source. The patches might later be
   corrected by other patches on top of them (patches were said to "grow
   scar tissue"). The result was often a convoluted {patch space} and
   headaches galore. 5. [Unix] the `patch(1)' program, written by Larry
   Wall, which automatically applies a patch (sense 3) to a set of source
   code.

   There is a classic story of a {tiger team} penetrating a secure
   military computer that illustrates the danger inherent in binary patches
   (or, indeed, any patches that you can't -- or don't -- inspect and
   examine before installing). They couldn't find any {trap door}s or any
   way to penetrate security of IBM's OS, so they made a site visit to an
   IBM office (remember, these were official military types who were
   purportedly on official business), swiped some IBM stationery, and
   created a fake patch. The patch was actually the trapdoor they needed.
   The patch was distributed at about the right time for an IBM patch, had
   official stationery and all accompanying documentation, and was
   dutifully installed. The installation manager very shortly thereafter
   learned something about proper procedures.


Source: The Jargon File