You’ll find examples of metaphors all around you, including in poems, songs, movies, and even everyday speech. Some metaphors can evoke powerful imagery. If you told someone that you were going through a “rollercoaster of emotions,” or that the free gift with purchase was the “icing on the cake” that day, they'd instantly understand what you were feeling.
Metaphors are a useful descriptive tool, but when the metaphorical meaning of a phrase has overcome the original image, it is said to have become a dead metaphor. Looking at some key examples of dead metaphors can help to better illustrate this point. “Illustrate” is used as a metaphor here too!