An event or situation foreshadows something that will happen later, often giving us a hint about what's coming.
When we talk about foreshadowing, we usually mean it in the context of stories like books or movies. Let's say you're watching a movie and you see a character get into a car accident earlier on. Later in the story, that same character gets hurt again - maybe more seriously this time. The first event, where they got into an accident, foreshadowed what happened later. It gave us a clue about what might happen next.
If you're writing or talking about stories, you might use the word "foreshadow" to describe how something that happens early on hints at what's going to happen later.
To presage, or suggest something in advance.
