The crossword solutions for the term MAP LINE: ABBR. are LAT (3 letters) and RTE (3 letters). LAT stands for Latitude, which is a geographic coordinate that specifies the north-south position of a point on the Earth's surface. RTE stands for Route, which is a path or course taken by a person or vehicle from one place to another. Both Latitude and Route are commonly used in maps to help people navigate from one place to another.