Source : Webster's Revised Unabridged Dictionary (1913)

Patch \Patch\, n. [OE. pacche; of uncertain origin, perh. for
   placche; cf. Prov. E. platch patch, LG. plakk, plakke.]
   1. A piece of cloth, or other suitable material, sewed or
      otherwise fixed upon a garment to repair or strengthen it,
      esp. upon an old garment to cover a hole.

            Patches set upon a little breach.     --Shak.

   2. Hence: A small piece of anything used to repair a breach;
      as, a patch on a kettle, a roof, etc.

   3. A small piece of black silk stuck on the face, or neck, to
      hide a defect, or to heighten beauty.

            Your black patches you wear variously. --Beau. & Fl.

   4. (Gun.) A piece of greased cloth or leather used as
      wrapping for a rifle ball, to make it fit the bore.

   5. Fig.: Anything regarded as a patch; a small piece of
      ground; a tract; a plot; as, scattered patches of trees or
      growing corn.

            Employed about this patch of ground.  --Bunyan.

   6. (Mil.) A block on the muzzle of a gun, to do away with the
      effect of dispart, in sighting.

   7. A paltry fellow; a rogue; a ninny; a fool. [Obs. or
      Colloq.] ``Thou scurvy patch.'' --Shak.

   {Patch ice}, ice in overlapping pieces in the sea.

   {Soft patch}, a patch for covering a crack in a metallic
      vessel, as a steam boiler, consisting of soft material, as
      putty, covered and held in place by a plate bolted or
      riveted fast.

Patch \Patch\, v. t. [imp. & p. p. {Patched}; p. pr. & vb. n.
   {Patching}.]
   1. To mend by sewing on a piece or pieces of cloth, leather,
      or the like; as, to patch a coat.

   2. To mend with pieces; to repair with pieces festened on; to
      repair clumsily; as, to patch the roof of a house.

   3. To adorn, as the face, with a patch or patches.

            Ladies who patched both sides of their faces.
                                                  --Spectator.

   4. To make of pieces or patches; to repair as with patches;
      to arrange in a hasty or clumsy manner; -- generally with
      up; as, to patch up a truce. ``If you'll patch a
      quarrel.'' --Shak.

Source : WordNet®

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}]

patch
     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 : Free On-Line Dictionary of Computing

patch
     
         1. 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. To insert a patch into a piece of code.
     
        3. [in the Unix world] A {diff}.
     
        4. A set of modifications to binaries to be applied by a
        patching program.  {IBM} 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 code}.  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.
     
        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 doors} 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.
     
        5. {Larry Wall}'s "patch" utility, which automatically applies
        a patch to a set of {source code} or other text files.  It
        accepts input in any of the four forms output by the {Unix}
        {diff} utility and uses many helpful {heuristics} to determine
        how to apply them.
     
        Diff and patch are the standard way of producing and applying
        updates to {Unix} files ditributed via {Usenet} and the
        {Internet}, both have been ported to other {operating
        systems}.
     
        See your nearest {GNU archive site}.
     
        [{Jargon File}]
     
        (1996-06-04)