Metaphor:    A Metaphor is a contracted simile.  It does not use "like" or "as" in its phrasing.

It is a word or phrase that is used to describe something or someone, by describing them as being something else.

Example 1  From everyday speech:

He is a little monster  ( He is not really a monster, but he is described as such to help us to recognise his character easily)

Example 2 From literature:

                         Outside the house an ash-tree hung its terrible whips,

                         And at night when the wind rose, the lash of the tree

                 Shrieked and slashed the wind, as  a ship's

                         Weird rigging in a storm shrieks hideously

                                                           from Discord in Childhood by D H Lawrence

NOTE:  Look at the way Lawrence develops his metaphors.  He introduces the branches of the tree as being like whips.  This gives us a feel both for the movement and the noise that they make.  He develops this in the second line by talking of the "lash" of the tree, shrieking and slashing.  There is an energy and ferociousness in this description .  He then continues with a simile of the tree resembling the rigging of a ship in a wild storm.  Think about the way you would normally think of a tree, and then consider how Lawrence has turned his tree into a vicious and threatening object.  He uses the metaphor to create mental images for us, and you can do the same in your writing.  

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