It’s vanishingly rare to encounter a student in secondary school who doesn’t know what a metaphor is. That said, it’s equally rare to find students who are able to define what a metaphor actually is. When pressed, they tend to say things like, “It when to say something is something else,” or “It’s saying something is something it isn’t,” or, even more commonly, “I know what it is but I don’t know how to explain it.”

Does any of this matter? After all, if students can spot a metaphor – and they usually can – why do they need to provide a precise definition?

I’m going to argue that the inability to define metaphor contributes to students being able to do little more than point them out. As always, the point of noticing a linguistic or structural device is be able to talk about its effect.

The literal meaning of metaphor – both in ancient and modern Greek – is to transport. Metaphorically, meaning is transported from one idea to another. There’s something rather exquisite about the fact that lorries in modern Greece are still called metaphores from meta (between or among) and phoros (carrying or bearing).

So, here’s the definition I favour: metaphor is language that transports meaning from one ‘place’ to another.

What makes a metaphor?

This brings us to the unwieldy sounding terms tenor, vehicle and ground.

Back in 1934, Cambridge professor I.A. Richards saw metaphor as, “a transaction between contexts”. In order to analyse the operations of metaphor he saw the necessity of naming these contexts and proposed the terms ‘tenor’ and ‘vehicle’: the tenor is the subject of the metaphor, the vehicle the source of its imagery. Without names for the parts of metaphor, he argued, we run the risk of confusing the relationship between tenor and vehicle for the relationship between the whole metaphor and its meaning.

We can also add the concept of ‘ground,’ the relationship between literal and metaphorical meanings. Considering tenor, vehicle and ground allows us to explain why a metaphor is (or is not) successful.

  • Tenor = the subject of the metaphor and its intended meaning
  • Vehicle = the language used to described the tenor
  • Ground = the relationship between the tenor and the vehicle

Again, etymology is useful in making sense of these terms. While, vehicle and ground are more or less obvious, tenor comes from the Latin verb tenere, ‘to hold’. I’ve found the following image a useful way to explain the relationship between this three components to students:

The vehicle ‘holds’ the tenor and transports it along the ground from one ‘place’ to another.

The best place to start seeing the relationship between tenors and vehicles is to examine a simile. Here’s one from Christina Rosetti’s poem of the same name, “My heart is like a singing bird.”

  • Tenor = Rossetti’s heart
  • Vehicle = “a singing bird”
  • Ground = we think of singing birds as beautiful and peaceful so we’re invited to think that Rossetti’s heart (here a metaphor for her emotional state) is in a beautiful peaceful place.

Some metaphors are as straightforward as similes, such as that in Wordsworth’s poem, ‘I wandered lonely as a cloud’:

  • Tenor = Wordsworth’s wanderings
  • Vehicle = a cloud
  • Ground = Just as clouds are randomly blown by the wind, so Wordsworth’s wandering is directionless and without intent.

By examining the ground of a metaphor, we can work out which qualities of the vehicle are being transferred to the tenor. For instance, clouds can be dark and result in rain, but unless otherwise stated we think of them as white and fluffy. This is the quality that is transferred from the vehicle to the tenor in Wordsworth’s metaphor.

But most metaphors are less straightforward, and this is where students run into difficulties. All too often, the tenor of a metaphor is unstated. For instance, in Paul Lawrence Dunbar’s ‘I know Why the Caged Bird Sings’ we have work out what the caged bird represents. This can be tricky without knowing that Dunbar was an African American writing in 1899. Knowing this we can then infer that he is likely to have regularly encountered overt racial discrimination and that he – and other black people – are ‘caged’ in that their potential is held back as a result of prejudice. The vehicle of the caged bird also invites us to consider what sorts of birds are locked in cages. No one would cage a common bird like a pigeon or a sparrow, instead a caged bird is more likely to be rare, beautiful or exotic. So the ground of this metaphor is that Dunbar sees himself – and by extension all black people – as both special and constrained by unfair circumstances.

Here’s a more complex example: “I have no spur to prick the sides of my intent, but only vaulting ambition”. The tenor here is Macbeth’s ambition to be king and the vehicle is a “spur”. The ground is that Shakespeare compares Macbeth’s desire to be king to riding a horse. There’s nothing wrong with ambition per se, but just as a spur is a rather cruel way to make a horse run faster, so murder is a reprehensible way of achieving one’s desires.

Sometimes metaphors work despite the disharmony of tenor and vehicle. Although metaphors struggle to work where there is little or no point of similarity, sometimes greater tension is produced by the ‘unlikeness’ than the ‘likeness’ of tenor and vehicle. Consider this line from Othello: “Steep’d me in poverty to the very lips”.

  • Tenor = poverty
  • Vehicle = the sea, or a vat of liquid
  • Ground = poverty, which should be a state of deprivation, is conceived of as being so much in abundance that Othello is at the point of drowning in it. This disharmony underlines Othello’s disturbed state of mind as he frets over Desdemona’s supposed infidelity.

We shouldn’t be able to drown in the lack of something, but Shakespeare’s startling combination of unlikenesses highlights Othello’s predicament. When a metaphor ‘works’ tenor and vehicle reinforce each other; meanings are transferred in both directions, enriching each other. In Othello’s case, the tenor (His poverty) takes on a liquid, clinging viscosity, while the vehicle (the sea) becomes an oxymoron that could never quench thirst.

We can also use tenor, vehicle and ground not just to consider figurative language, but to unpick students’ understanding of concepts like character and theme. If we think of a character as a vehicle, we’re invited to consider the tenor they are intended to represent. We could argue that Inspector Goole is a vehicle for socialism, the Lord Capulet is a vehicle for patriarchy, or that Scrooge is a vehicle both for miserliness and redemption. On the other hand, themes are tenors in search or a vehicle. If we say that Jekyll and Hyde is about the battle between good and evil, the vehicle is the transformation of Dr Jekyll into Mr Hyde. If we say that one of themes of Macbeth is chaos and disorder, its vehicles could be the murder of a king or the intrusion of the supernatural into the ‘real’ world. Again, the ground is what makes these vehicles successful ways to depict their tenors.

Giving students names for the ‘parts’ of metaphor is a first step to understanding the metaphorical nature of the constructed world of language and literature. If, on the other hand, all we do is direct students to pick out metaphors from the texts they study, we limit all but the most advantaged to a circumscribed ability to perceive the cracks between the literal and figurative. They may be able to notice the vehicle bobbing on the surface of a text without grasping that there’s a tenor lying beneath. Knowing that every vehicle must possess a tenor prompts students to consider what it may be. This, in turn, makes more of the vehicle visible. By introducing the concept of ground, we prompt students to ‘show their working out’ and make visible the connections they infer between tenor and vehicle.

Introducing these terms to students to enhance their ability to analyse metaphor is only useful if you commit. You have to invest curriculum time to repeatedly using the terms and modelling their utility before it begins to pay off. Also, a word of caution. I.A. Richards himself warned that “a metaphor may work admirably without our being able … to say how it works or what is the ground of the shift.” Nevertheless, thinking in terms of topic, vehicle and grounds can be a useful way for students to think about the relationship between the components of a metaphor and will help prompt them to move beyond noticing into more analytic analogising.


I.A. Richards, The Philosophy of Rhetoric.