Crossword clues for Defensive structure. 5 letters:FORTSDefensive structuresREDANDefensive structure.FORTDefensive structureFORTOater defense structureFORTRESSDefensive structureRAMPARTDefensive structureSTOCKADEDefensive structure.MOATDefensive structure encircling a castlePALISADEDefensive structureSEAWALLSCoastal defense structuresFORTDefense structure