The term BLDG. BOSS is an acronym for Building Supervisor, which is a job title typically given to someone who is responsible for the maintenance and upkeep of a building or facility. The crossword solution for this term is SUPT, which is an abbreviation for Superintendent, which is another job title that is similar to Building Supervisor. The Superintendent is usually in charge of a larger facility or multiple buildings, and is responsible for overseeing the operations of the entire facility.