simile
A comparison using like or as to describe something.
A simile is a figure of speech that compares two different things using the words “like” or “as.” When you say “her smile was as bright as the sun” or “he ran like the wind,” you're using similes to help someone picture exactly what you mean.
Similes make your writing and speaking more vivid and interesting. Instead of saying “the cat was quiet,” you might say “the cat moved as quietly as a shadow.” Instead of “she was brave,” you could write “she was brave as a lion.” The comparison helps people feel and imagine what you're describing more powerfully.
Writers use similes constantly. In Charlotte's Web, E.B. White describes Wilbur's tail as “tightly curled, like a corkscrew.” In The Lion, the Witch and the Wardrobe, C.S. Lewis writes that the word “Aslan” made Peter feel “brave and adventurous, like hearing a beautiful piece of music.” These comparisons stick in your mind far better than plain description would.
The key difference between a simile and a metaphor is that similes use “like” or “as” to make their comparison explicit, while metaphors state the comparison directly. “Her eyes were like diamonds” is a simile. “Her eyes were diamonds” is a metaphor.