You see, it's really quite simple. A simile is just a mode of comparison employing 'as' and 'like' to reveal the hidden character or essence of whatever we want to describe, and through the use of fancy, association, contrast, extension, or imagination, to enlarge our understanding or perception of human experience and observation.
Norton Juster, As Silly as Knees, As Busy as Bees: An Astounding Assortment of Similes
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