Saying one thing through another, without a word of comparison: instead of saying that something is like another thing, one says that it is. The image transfers to the subject the qualities of the thing it has been identified with.
In Romeo and Juliet
A pair of star-crossed lovers take their life
The "star-crossed" phrase makes fate a hostile star that has followed the lovers since birth. The image turns bad luck into something fixed in the sky, beyond the reach of the two.
Act I: The brawl and the ball, the Chorus
my mind misgives / Some consequence yet hanging in the stars
Act I: The brawl and the ball, Romeo
Now old desire doth in his deathbed lie, / And young affection gapes to be his heir
Act II: The garden and the wedding, the Chorus
O serpent heart, hid with a flowering face!
Act III: Mercutio, Tybalt, and the banishment, Juliet
See what a scourge is laid upon your hate, / That heaven finds means to kill your joys with love.
Act V: The tomb and the reconciliation, the Prince
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