Castaway

A castaway is a person who is cast adrift or ashore. While the situation usually happens after a shipwreck, some people voluntarily stay behind on a deserted island, either to evade their captors or the world in general. Alternatively, a person or item can be cast away, meaning rejected or discarded. Note that when a person was left ashore as punishment, usually the term maroon (or marooned) was used.