The term 'Las Vegas Illumination' refers to the iconic NEON lights that adorn the city of Las Vegas. The crossword solution for this term is 'NEON, ' which is an acronym for 'NEON Electric Outdoor Advertising.' NEON lighting has been used in Las Vegas since the 1930s, and it has become a symbol of the city's vibrant nightlife. NEON signs are used to advertise casinos, hotels, restaurants, and other attractions, and they are a major part of the city's identity.