The term 'Desert Rat' is a nickname given to the British soldiers who fought in the North African Campaign during World War II. The term is also used to refer to any person who lives in a desert environment. The crossword solution for this term is 'JERBOA, ' which is a small rodent native to desert regions of North Africa and Asia. Jerboas have long hind legs and a long tail, allowing them to jump great distances and move quickly across the desert terrain.