The crossword solution for the term BOS is LOGAN. LOGAN is a city in Cache County, Utah, United States. It is the county seat of Cache County and the principal city of the Logan metropolitan area, which includes Cache County and Franklin County, Idaho. The population was 48, 174 at the 2010 census, with an estimated population of 50, 721 in 2018. Logan is the location of the main campus of Utah State University.