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a. a small plot of land
b. its produce
2. a district for which particular officials, such as social workers or policemen, have responsibility
3. Pathol any discoloured area on the skin, mucous membranes, etc., usually being one sign of a specific disorder
4. Med
a. a protective covering for an injured eye
b. any protective dressing
5. Computing a small set of instructions to correct or improve a computer program


(computer science)
To modify a program or routine by inserting a machine language correction in an object deck, or by inserting it directly into the computer through the console.
The section of coding inserted in this way.
A temporary connection between jacks or other terminations on a patch board.


1. In stone masonry, a compound used to fill natural voids or to replace chips and broken corners or edges in fabricated pieces of cut stone; applied in plastic form; mixed or selected to match the color and texture of the stone.
2. In carpentry and joinery, a piece of wood or veneer glued into a recess to replace defective portions or voids; an insert or plug.


court fool of Elizabeth, wife of Henry VII. [Br. Hist.: Brewer Handbook, 380]
See: Clowns


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 program, which automatically applies a patch to a set of source code or other text files. Patch accepts input in any of the four forms output by the Unix diff utility. When the files being patched are not identical to those on which the diffs were based, patch uses heuristics to determine how to proceed.

Diff and patch are the standard way of producing and applying updates under Unix. Both have been ported to other operating systems.

Patch Home.


A modification (noun) of software or to modify (verb) software. In the past, a patch used to mean changing actual executable, machine instructions, but today more often than not, it means replacing an executable module in its entirety such as an .EXE or .DLL file. A profusion of patches to an application implies that its logic was poorly designed in the first place.

Although the term typically refers to fixing a problem, a patch may also refer to a general enhancement because the two scenarios have become blurred. For example, a security "enhancement" is often a fix for a vulnerability in the program. In addition, software vendors like to announce something new in an update other than just fixing problems. Therefore, applying patches often refers to both fixes and new features. See patch management and spaghetti code. See also MIDI patch.
References in classic literature ?
This he undoubtedly had learnt from Anna-- and then Sandford was very much like Stanley--his patch, his dress, his air--every thing about him united to confirm her impressions; and Julia, at the same time she resolved to conduct herself towards him in their journey with a proper feminine reserve, thought she could do no less to a man who submitted to so much to serve her, than to suffer him to perceive that she was not entirely insensible to the obligation.
A score and more of barefoot friars were there, and some that looked like tinkers, and some that seemed to be sturdy beggars and rustic hinds; and seated upon a mossy couch was one all clad in tattered scarlet, with a patch over one eye; and in his hand he held the golden arrow that was the prize of the great shooting match.
The grey, hot mist, the whitewashed cabin, the long, ugly potato patch, the weird, pathetic figure of that old man from whose brain the light of life had surely passed for ever.
He had relinquished his digging and, after a long, stealthy glance towards the house, had advanced to the extreme boundary of the potato patch.
We've planned to get ahead, though, and then some day we'll buy a patch of land and stay with it.
Then out rides our own little hothead with the patch over his eye, and my Lord Audley with his four Cheshire squires, and a few others of like kidney, and after them went the prince and Chandos, and then the whole throng of us, with axe and sword, for we had shot away our arrows.
Reuben Limbrick answered, "So much the worse for the neighborhood"--and persisted in calling his property, "Salt Patch.
It proved to be a great aggravation of Hester's offenses, in the eyes of Hester's relatives, when it was discovered that she possessed a life-interest in Salt Patch, and an income of two hundred a year.
The patch of light fell clear of the striped blanket, and began to cover the shawl that lay over her feet.
When I see a patch of colour, it seemed to me that the colour is not psychical, but physical, while my seeing is not physical, but psychical.
They were all flying from the beehives behind the hedge, and they disappeared over the hemp patch in the direction of the marsh.
He passes under the name of Steve Wilson, and he is lodging at Hobson's Patch.