The crossword solution for the term MEX is MADAMES, which stands for Mexican Air Defense and Maritime Surveillance System. This system is a joint effort between Mexico and the United States to monitor air and maritime traffic in the Gulf of Mexico. The SRAS (4 letters) stands for the Spanish acronym for the system, Sistema de Vigilancia Aerea y Marítima de Mexico. The system was established in 2004 and is designed to provide real-time information on air and maritime traffic in the region.