The term 'NAUTICAL SHELTER' can be broken down into two words: 'NAUTICAL' and 'SHELTER'. The word 'NAUTICAL' is defined as relating to ships, sailing, navigation, or seamanship. The word 'SHELTER' is defined as a place of refuge or safety. The crossword solution for this term is 'LEE', which is defined as the side or direction away from the wind. Therefore, the term 'NAUTICAL SHELTER' can be defined as a place of refuge or safety away from the wind, typically found on a ship or boat.