Speakers and writers use metaphors to communicate in more interesting and descriptive ways. Like similes, metaphors also compare things that are mostly unalike, but that have qualities in common. The different between similes and metaphors are that metaphors do not include the words “like” or “as”. They describe something as if it were something else, for example, “Books are the keys to your imagination”. By using this metaphor, the writer describes books as having the ability to open doors in your mind so that you can use your imagination just as a key unlocks a door.
In the above metaphor, the comparison is implied – the reader has to draw from their experience or knowledge of keys to understand it. You have to know that keys open things that were locked like doors.
Another example of an implied comparison is when the writer doesn’t explain exactly what the two things are that are being compared: in the metaphor “I could hear laughter cascading down the passage”, the word ‘cascading’ is comparing the sound of laughter to the sound of water rushing over rocks. Although the writer does not mention the word ‘water’ – as readers we know that this is a word that is usually used to describe water.
Sometimes writers use an idea for a metaphor and repeat it a few times through their poem or passage. This is called an extended metaphor. For example, a writer may compare a business to a plant: it went through a dry patch and withered, but now it is healthy and flourishing.