A metaphor is a trope or figure of speech in which an implied comparison is made between two unlike things that actually have something in common. A metaphor expresses the unfamiliar (the tenor) in terms of the familiar (the vehicle). When Neil Young sings, "Love is a rose," the word "rose" is the vehicle for the term "love," the tenor.

The word metaphor itself is a metaphor, coming from a Greek term meaning to "transfer" or "carry across." Metaphors "carry" meaning from one word, image, idea, or situation to another.

Conventional Metaphors

Some people think of metaphors as little more than the sweet stuff of songs and poems—such as love is a jewel, a rose, or a butterfly. But people use metaphors in everyday writing and speaking. You can't avoid them: They are baked right into the English language.

Calling a person a "night owl" or an "early bird" is an example of a common or conventional metaphor—one that most native speakers readily understand. Some metaphors are so prevalent that you may not even notice that they are metaphors. Take the familiar metaphor of life as a journey. You can find it in advertising slogans:

"Life is a journey, travel it well."

—United Airlines

"Life is a journey. Enjoy the Ride."

—Nissan

"The journey never stops."

—American Express

Many other categories of metaphors enhance the English language.

Other Types

Metaphor types range from conceptual and visual to dead metaphors, which lose their impact and meaning due to overuse. (You might say, metaphorically, they are done to death.) A specific type of metaphor is even used in psychological counseling. Following are the main types of this figure of speech:

Absolute: a metaphor in which one of the terms (the tenor) can't be readily distinguished from the other (the vehicle). Your Dictionary notes that these metaphors compare two things that have no obvious connection but are joined to make a point such as: “She is doing a tightrope walk with her grades this semester.” Of course, she is not a circus performer, but the absolute metaphor—tightrope walk—clearly makes the point about the precarious nature of her academic standing.

Complex: a metaphor in which the literal meaning is expressed through more than one figurative term (a combination of primary metaphors). The website Changing Minds says that a complex metaphor occurs where a simple metaphor is based on a "secondary metaphoric element," such as using the term "light" to indicate understanding, as in the sentence "He threw light on the subject." Changing Minds also gives these examples:

That lends weight to the argument.

They stood alone, frozen statues on the plain.

The ball happily danced into the net.

Conceptual: a metaphor in which one idea (or conceptual domain) is understood in terms of another—for example:

You're wasting my time.

This gadget will save you hours.

I don't have the time to give you.

In the last sentence, for example, you can't actually "have" or "give" time, but the concept is clear from the context.

​Creative: an original comparison that calls attention to itself as a figure of speech. It is also known as a poetic, literary, novel, or unconventional metaphor, such as:

"Her tall black-suited body seemed to carve its way through the crowded room."

—Josephine Hart, "Damage"

"Fear is a slinking cat I find / Beneath the lilacs of my mind."

—Sophie Tunnell, "Fear"

"The apparition of these faces in the crowd; / Petals on a wet, black bough."

—Ezra Pound, "In a Station of the Metro"

A body can't "carve" anything, fear is not a slinking cat (and no mind contains lilacs), and faces are not petals, but the creative metaphors paint vivid pictures in the reader's mind.

Extended: a comparison between two unlike things that continues throughout a series of sentences in a paragraph or lines in a poem. Many lyrical writers use extended metaphors, such as this drawn-out circus image by a best-selling author:

"Bobby Holloway says my imagination is a three-hundred-ring circus. Currently, I was in ring two hundred and ninety-nine, with elephants dancing and clowns cartwheeling and tigers leaping through rings of fire. The time had come to step back, leave the main tent, go buy some popcorn and a Coke, bliss out, cool down."

—Dean Koontz, "Seize the Night"

Dead: a figure of speech that has lost its force and imaginative effectiveness through frequent use, such as:

"Kansas City is oven hot, dead metaphor or no dead metaphor."

—Zadie Smith, "On the Road: American Writers and Their Hair"

Mixed: a succession of incongruous or ludicrous comparisons—for example:

"We'll have a lot of new blood holding gavels in Washington."

—Former U.S. Rep. Jack Kingston (R-Ga.), in the Savannah Morning News, Nov. 3, 2010

"That's awfully thin gruel for the right wing to hang their hats on."

— MSNBC, Sept. 3, 2009

Primary: A basic intuitively understood metaphor—such as knowing is seeing or time is motion—that may be combined with other primary metaphors to produce complex metaphors.

Root: An image, narrative, or fact that shapes an individual's perception of the world and interpretation of reality, such as:

"Is the whole universe a perfect machine? Is the society an organism?"

—Kaoru Yamamoto, "Too Clever for Our Own Good: Hidden Facets of Human Evolution"

Submerged: a type of metaphor in which one of the terms (either the vehicle or tenor) is implied rather than stated explicitly:

Alfred Noyes, "The Highwayman"

"The moon was a ghostly galleon tossed upon cloudy seas."

Therapeutic: a metaphor used by therapists to assist clients in the process of personal transformation. Getselfhelp.co.uk, a British website that offers psychotherapy resources and information, gives this example of passengers on a bus:

"You can be in the driving seat, whilst all the passengers (thoughts) are being critical, abusive, intrusive, distracting, and shouting directions, or sometimes just plain nonsense. You can allow those passengers to shout and chatter noisily, whilst keeping your attention focused on the road ahead, heading towards your goal or value."

The metaphor aims to help present someone seeking help with a way to stay focused on what's important by shutting out distracting, negative thoughts.

Visual: the representation of a person, place, thing, or idea by way of a visual image that suggests a particular association or point of similarity. Modern advertising relies heavily on visual metaphors.

For example, in a magazine ad a few years ago for the banking firm Morgan Stanley, a man is pictured bungee jumping off a cliff. Two words serve to explain this visual metaphor: A dotted line from the jumper's head points to the word "You," while another line from the end of the bungee cord points to "Us." The metaphorical message—of the safety and security provided by the firm in times of risk—is conveyed through a single dramatic image.

The Value of Metaphors

We need metaphors, James Grant wrote in his article "Why Metaphor Matters" published on OUPblog, a website operated by Oxford University Press. Without metaphors, "many many truths would be inexpressible and unknowable." Grant noted:

"Take Gerard Manley Hopkins’s exceptionally powerful metaphor of despair: 'selfwrung, selfstrung, sheathe- and sheterless, / thoughts against thoughts in groans grind.' How else could precisely this kind of mood be expressed? Describing how things appear to our senses is also thought to require metaphor, as when we speak of the silken sound of a harp, the warm colours of a Titian, and the bold or jolly flavour of a wine."

Science advances by the use of metaphors, Grant added—of the mind as a computer, of electricity as a current, or of the atom as a solar system. When using metaphors to enrich writing, consider how these figures of speech are more than just ornaments or decorative accessories. Metaphors are also ways of thinking, offering readers (and listeners) fresh ways of examining ideas and viewing the world.

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