Foreshadowing is when something happens within a story which shows that something else will happen later in the story. (indicator that something will happen)
Foreshadowing is like a clue that an event will take place within a story.
An example of foreshadowing comes from Shakespeare’s Romeo and Juliet where Juliet is afraid for Romeo’s safety from the guards. He says, “Life were better ended by their hate, Than death prorogued, wanting of thy love.”
Here he states that he would rather have her love and die sooner than to live longer and be without her love. In the end, he dies and has her love. This foreshadows his death.
Example referenced from: http://literarydevices.net/foreshadowing/