The term 'MAYOR'S DOMAIN' can be broken down into two parts: the mayor and their domain. The mayor is the elected leader of a CITY, responsible for making decisions that affect the citizens of the CITY. The domain of the mayor is the area of responsibility they have, which includes overseeing the CITY's budget, managing public services, and representing the CITY in negotiations with other governments. The crossword solution for this term is CITY, which is a four-letter word that refers to a large urban area with a significant population.