A metaphor is a figure of speech that, for rhetorical effect, directly refers to one thing by mentioning another.[1] It may provide (or obscure) clarity or identify hidden similarities between two different ideas. Metaphors are usually meant to create a likeness or an analogy.[2]
Analysts group metaphors with other types of figurative language, such as antithesis, hyperbole, metonymy, and simile.[3] “Figurative language examples include “similes, metaphors, personification, hyperbole, allusions, and idioms.””[4] One of the most commonly cited examples of a metaphor in English literature comes from the "All the world's a stage" monologue from As You Like It:
All the world's a stage,
And all the men and women merely players;
They have their exits and their entrances
And one man in his time plays many parts,
His Acts being seven ages. At first, the infant...
—William Shakespeare, As You Like It, 2/7[5]
This quotation expresses a metaphor because the world is not literally a stage, and most humans are not literally actors and actresses playing roles. By asserting that the world is a stage, Shakespeare uses points of comparison between the world and a stage to convey an understanding about the mechanics of the world and the behavior of the people within it.
In the ancient Hebrew psalms (around 1000 B.C.), one finds vivid and poetic examples of metaphor such as, "The Lord is my rock, my fortress and my deliverer; my God is my rock, in whom I take refuge, my shield and the horn of my salvation, my stronghold" and "The Lord is my shepherd, I shall not want". Some recent linguistic theories view all language in essence as metaphorical.[6] The etymology of a word may uncover a metaphorical usage which has since become obscured with persistent use - such as for example the English word " window", etymologically equivalent to "wind eye".[7]
The word metaphor itself is a metaphor, coming from a Greek term meaning 'transference (of ownership)'. The user of a metaphor alters the reference of the word, "carrying" it from one semantic "realm" to another. The new meaning of the word might derive from an analogy between the two semantic realms, but also from other reasons such as the distortion of the semantic realm - for example in sarcasm.
[...] a figure of speech in which a word or phrase literally denoting one kind of object or idea is used in place of another to suggest a likeness or analogy between them [... .]
[...] ANTITHESIS; HYPERBOLE; METONYMY; SIMILE are all species of metaphor.
If you look at our ordinary language, it's replete with synesthetic metaphors, cross-sensory metaphors such as for example if you said cheddar cheese is sharp. [...] So I'm going to argue in fact synesthesia has very broad implications. It might tell you about things like metaphor and how language evolved in the brain, maybe even the emergence of abstract thought that us humans, human beings are very good at.