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FOUR RHETORICAL FIGURES OF SPEECH
Metaphor is used to make a comparison by explaining one thing in terms of another. This is a way of introducing a new concept in terms of something already existing. So don’t bring your bucket and spade to a sandpit for start-ups.
Metonymy is a change of name with an association of the same meaning. Churchill is using this device when he refers to his book as a monster. Hollywood refers to the movie industry. Washington means the government.
Synecdoche refers to something by the name of one of its parts. The pen is mightier than the sword. (But don’t insist on that when facing a swordsman.) The pen stands for the power of the written word, and the sword is military might.
Irony is used for comic effect by saying the opposite of what is meant. Irony pokes fun at the status quo because values have shifted. It has elements of play, the stage seeking to emerge. Irony is a trigger for generating new meaning.