A metaphorical extension is the "extension of meaning in a new direction" through popular adoption of an original metaphorical comparison.
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Metaphorical extension is almost a universal and natural process in any language undergone by every word. In general, it's not even perceived in everyday usage as meaning change. When it is least obvious, users don't even see it as extending the meaning of a word. Consider the example of illuminate: it originally meant "to light up" something dim or dark, but has evolved to mean "to clarify", "to edify". After a while these new meanings seem so natural as to be integral parts of the word, where senses such as "to celebrate" and "to adorn a page with designs" seem like more obvious additions.
Radiation
According to linguist Jeffrey Henning:
Radiation is metaphorical extension on a grander scale, with new meanings radiating from a central semantic core to embrace many related ideas. The word head originally referred to that part of the human body above the rest. Since the top of a nail, pin or screw is, like the human head, the top of a slim outline, that sense has become included in the meaning of head. Since the bulb of a cabbage or lettuce is round like the human head, that sense has become included in the meaning of head. Know where I'm headed with this? The meaning of the word head has radiated out to include the head of a coin (the side picturing the human head), the head of the list (the top item in the list), the head of a table, the head of the family, a head of cattle, $50 a head.
Other words that have similarly radiated meanings outward from a central core include the words fire, root and sun.
Examples
A crane at a construction site was given its name by comparison to the long-necked bird of the same name. When the meaning of the word daughter was first extended from that of "one's female child" to "a female descendant" (as in daughter of Eve), the listener might not have even noticed that the meaning had been extended.
The late Admiral, mathematician, and computer pioneer, Grace Murray Hopper
Grace Brewster Hopper (; December 9, 1906 – January 1, 1992) was an American computer scientist, mathematician, and United States Navy rear admiral. One of the first programmers of the Harvard Mark I computer, she was a pioneer of compu ...
, frequently repeated a favorite amusing story in front of many audiences about an early computer that experienced an episode where it kept calculating incorrectly. When technicians examined the machine's hardwired logic (the wiring, in the World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...
era computer), a huge moth was discovered such that its body was shorting out one of the vacuum tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied.
The type kn ...
and relay
A relay
Electromechanical relay schematic showing a control coil, four pairs of normally open and one pair of normally closed contacts
An automotive-style miniature relay with the dust cover taken off
A relay is an electrically operated swit ...
circuits and causing the repetitive fault, and so may have played a key role in popularizing the term which was in use in hardware engineering from at least Edison
Thomas Alva Edison (February 11, 1847October 18, 1931) was an American inventor and businessman. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These invention ...
's time (see Computer bug#Etymology). Since the Admiral's speeches, both hardware faults and software errors are now routinely referred to as "bugs", and getting the flaws out of a product is known as'' 'debugging
In computer programming and software development, debugging is the process of finding and resolving ''bugs'' (defects or problems that prevent correct operation) within computer programs, software, or systems.
Debugging tactics can involve in ...
' ''the system. Her team almost certainly coined the latter term.[ Computer bug#Etymology] A particular type of software program designed to aid software development is known as a "debugger
A debugger or debugging tool is a computer program used to test and debug other programs (the "target" program). The main use of a debugger is to run the target program under controlled conditions that permit the programmer to track its execut ...
" complements the program known as a compiler
In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that ...
, the first of which was developed by G.M. Hopper.
The use of bug to refer to a computer error in logic was a ''metaphorical extension'' that has become so popular that it is now part of the regular meaning of "bug". The computer industry has a host of words whose meaning has been extended through such metaphors, including "mouse
A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...
" for possessing a 'tail' similar to said rodent now used widely for these computer input devices—even though the more modern wireless
Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The mos ...
ones have lost the metaphorical tail entirely.
See also
* Pataphor
* Extended metaphor
References
{{DEFAULTSORT:Metaphorical Extension
Extension
Extension, extend or extended may refer to:
Mathematics
Logic or set theory
* Axiom of extensionality
* Extensible cardinal
* Extension (model theory)
* Extension (predicate logic), the set of tuples of values that satisfy the predicate
* Ext ...