A castaway's home can be any of a variety of places, depending on the size and type of island. The four possible solutions for this crossword are ISLE, HUT, Island, and ATOLL. An ISLE is a small island, usually no more than a few miles in diameter. A HUT is a small, primitive dwelling, often made of natural materials such as wood or straw. An Island is a large landmass surrounded by water, and an ATOLL is a ring-shaped island, typically formed from coral. An ISLET is a very small island, usually no more than a few hundred feet in diameter.