An extended metaphor, also known as a conceit or sustained metaphor, is when an author exploits a single metaphor or analogy at length through multiple linked vehicles, tenors, and grounds. Tenor is the subject of the metaphor, vehicle is the image or subject that carries the weight of the comparison, and ground is the shared proprieties of the two compared subjects. Another way to think of extended metaphors is in terms of implications of a base metaphor. These implications are repeatedly emphasized, discovered, rediscovered, and progressed in new ways.
Symbolism is a common theme of extended metaphors. This is often seen in William Shakespeare's work. For example, in Sonnet 18 the speaker offers an extended metaphor which compares his love to Summer. Shakespeare also makes use of extended metaphors in Romeo and Juliet, most notably in the balcony scene where Romeo offers an extended metaphor comparing Juliet
This poem can only be understood if the reader has knowledge of the “life-is-a-journey” metaphor. That knowledge includes understanding of other grounds between the tenor (life) and vehicle (journey) that are not as transparent in this poem. Holyoak (2005) gives examples of these grounds, “person is a traveler, purposes are destinations, actions are routes, difficulties in life are impediments to travel, counselors are guides, and progress is the distance traveled.”
In "The Thought-Fox", Ted Hughes uses the extended metaphor that the idea he struggles to find is actually a fox. By using an extended metaphor, it becomes more convincing.
The pataphor (Spanish: patáfora, French: pataphore), is a term coined by writer and musician Pablo Lopez ("Paul Avion"), for an unusually extended metaphor based on Alfred Jarry's "science" of pataphysics. As Jarry claimed that pataphysics existed "as far from metaphysics as metaphysics extends from regular reality", a pataphor attempts to create a figure of speech that exists as far from metaphor as metaphor exists from non-figurative language. Whereas a metaphor is the comparison of a real object or event with a seemingly unrelated subject in order to emphasize the similarities between the two, the pataphor uses the newly created metaphorical similarity as a reality on which to base itself. In going beyond mere ornamentation of the original idea, the pataphor seeks to describe a new and separate world, in which an idea or aspect has taken on a life of its own.
Like pataphysics itself, pataphors essentially describe two degrees of separation from reality (rather than merely one degree of separation, which is the world of metaphors and metaphysics). The pataphor may also be said to function as a critical tool, describing the world of "assumptions based on assumptions", such as belief systems or rhetoric run amok. The following is an example.
Tom and Alice stood side by side in the lunch line.
Tom and Alice stood side by side in the lunch line; two pieces positioned on a chessboard.
Tom took a step closer to Alice and made a date for Friday night, checkmating. Rudy was furious at losing to Margaret so easily and dumped the board on the rose-colored quilt, stomping downstairs."
Thus, the pataphor has created a world where the chessboard exists, including the characters who live in that world, entirely abandoning the original context.
The pataphor has been subject to commercial interpretations, usage in speculative computer applications, applied to highly imaginative problem solving methods and even politics on the international level or theatre The Firesign Theatre (a comedy troupe whose jokes often rely on pataphors). There is a band called Pataphor and an interactive fiction in the Interactive Fiction Database called "PataNoir," based on pataphors.
Pataphors have been the subject of art exhibits, as in Tara Strickstein's 2010 "Pataphor" exhibit at Next Art Fair/Art Chicago.
There is also a book of pataphorical art called Pataphor by Dutch artist Hidde von Schie.
It is worth noting that a pataphor is not the traditional metaphorical conceit but rather a set of metaphor built upon an initial metaphor, obscuring its own origin rather than reiterating the same analogy in myriad ways.