Use thousandth in a sentence. 1  coming last in a series of a thousand; 1,000th. 2  designating any of the thousand equal parts of something.
For other uses, see Brigham City (disambiguation). Brigham City is a city in Box Elder County, Utah, United States. The population was 17,899 at the 2010 census. It is the county seat of Box Elder County. It lies on the western slope of the Wellsville Mountains, a branch of the Wasatch Range at the western terminus of Box Elder Canyon.
Brigham City, UT Population and Races. As of 2010-2014, the total population of Brigham City is 18,264, which is 4.90% more than it was in 2000. The population growth rate is much lower than the state average rate of 27.98% and is much lower than the national average rate of 11.61%.