What is an example of a contextual symbol explain

Contextual symbol is a word or object that stands for something else just in the story or situation.

For example . Do you know the sign with a skull and 2 bones crossed behind him) I think you do. . The skull and crossbones stand for poison. So, if you see the symbol( you can try typing it on google) on a box or bucket, please don’t eat what is inside of the container.
It's that simple... Hope it helped