Metaphor: From the Greek for “to transfer,” a figure of speech (more specifically a trope) that associates two distinct things without using a connective word to link the vehicle and the tenor. Metaphor is distinguished from simile, another trope that associates two distinct things by using a connector such as like or as. To say “That child is a mouse” is to use a metaphor, whereas to say “That child is like a mouse” is to use a simile. In either case, the mouse is the vehicle, the image being used to represent the child, which is the tenor, or subject of the figure.

Theorists ranging from the fourth-century B.C. Greek philosopher Aristotle to the twentieth-century English literary critic I. A. Richards have argued that metaphors equate the vehicle with the tenor instead of simply comparing the two. This identification of vehicle and tenor can provide both linguistic punch and enhanced meaning. For instance, by saying “Last night I plowed through a book” rather than “Last night I read a book,” you convey not only that you read a book but also how you read it, for to read a book as a plow rips through earth is surely to read in a relentless, unreflective way. Note that, in the sentence above, a new metaphor — “rips through” — has been used to explain an old one, demonstrating just how thick (another metaphor) language is with metaphors.

Metaphors may be classified as direct or implied. A direct metaphor, such as “That child is a mouse,” expressly identifies both tenor and vehicle. An implied metaphor, by contrast, specifies only the vehicle, leaving the tenor to be inferred from the context of the sentence or passage. For instance, in the sentence “Last night I plowed through a book,” the tenor — the act of reading — is implied. A mixed metaphor exists when multiple, very different — and sometimes incongruous — vehicles are used to represent the same tenor. In his essay “Politics and the English Language” (1946), George Orwell gave as an example of mixed metaphor the sentence “The fascist octopus has sung its swan song.”

Metaphors may also be classified as living, dead, or dormant — three descriptions that are themselves metaphors. A dead metaphor, also called a frozen metaphor, is a word or phrase that is no longer recognized as a metaphor because it has become so familiar (“running water”). A dormant metaphor is a word or phrase in the process of dying as a metaphor (the “bottom line”).

Traditionally, metaphor has been viewed as the most significant of the five principal tropes, the others being simile, metonymy, personification, and synecdoche.

FURTHER EXAMPLES: Common legal metaphors include “black-letter law,” calling a long-standing constitutional principle a “fixed star,” and seeking to “square” judicial precedents. Victorian poet Matthew Arnold makes the sea a metaphor for religious faith in his poem “Dover Beach” (1867):

The Sea of Faith

Was once, too, at the full, and round earth’s shore… .

In “Cypresses” (1923), modernist poet D. H. Lawrence metaphorically transforms the tall, thin, blackish-green trees so familiar in European paintings into “supple, brooding, softly-swaying pillars of dark flame.” In John Updike’s novel Rabbit, Run (1960), metaphors reveal the anxieties and obsessions of protagonist Henry “Rabbit” Angstrom, who thinks of his car as “a sheath for the knife of himself” and of Chinese food as “Candy. Heaped on a smoking breast of rice.” In Carrie Fisher’s Postcards from the Edge (1987), the protagonist is told that

“In India they say that the body is the envelope of the spirit, and the spirit, I guess, is essentially who you are. Well, we live in a city of envelopes. The thing that’s terrific about you is that you are a letter. I mean, it takes a letter to know a letter, and I can see we’re really two letters in a town of envelopes… .”

Tom Petty’s song title “Love Is a Long, Long Road” (1989) is metaphorical, as is the Rolling Stones’ song “She’s So Cold” (1980), in which a reference to a bleeding volcano mixes two vehicles (wound and eruption) to represent one tenor (emotional overflow). Rapper Mos Def used mining metaphors in the first verse of “Travellin’ Man” (1998) to discuss rhyming, comparing the search for the perfect rhyme to coal mining and finding a diamond. In his literary thriller Descent (2015), Tim Johnston uses metaphor to describe a character’s physical response to emotional tension: “She didn’t have to glance at the sheriff; he’d already left the room. She mated her hands before her… .” Some metaphors are so apt that they are used repeatedly in everything from conversation to popular fiction. In Mary Kubica’s The Good Girl (2014), memory is described in conventional metaphorical terms: “something passes through her — a wave of recollection — and then it’s gone as soon as it came.”