Metaphor
Being visual does not just mean describing; telling us facts; indicating shapes, colors, and specific details. Often the vividness of the picture in our minds depends on comparisons made through figures of speech. What we are trying to imagine is pictured in terms of something else familiar to us, and we are asked to think of one thing as if it were something else. Many such comparisons, in which something is pictured or figured forth in terms of something already familiar to us, are taken for granted in daily life. Things we can¡¯t see or that aren¡¯t familiar to us are imaged as things we already know; for example, God is said to be like a father; Italy is said to be shaped like a boot; life is compared to a forest, a journey, or a sea. When the comparison is implicit, describing something as if it were something else, it is called a metaphor.
metaphor
the most important and widespread *FIGURE OF SPEECH in which one thing, idea£¬or action is referred to by a word or expression normally denoting another thing£¬idea£¬or action£¬so as to suggest common quality shared by the two. In metaphor£¬this resemblance is assumed as an imaginary identity rather than directly stated as a comparison... Modern analysis of metaphors and similes distinguishes the primary literal term(called ¡®*TENOR¡¯) from the secondary figurative term (the ¡®vehicle¡¯) applied o it: in the metaphor the road of life, the tenor is life, and the vehicle is the road. (From the Concise Oxford Dictionary of Literary Terms)