Brilliant is an unincorporated community and census-designated place in eastern Jefferson County, Ohio, United States, along the Ohio River. It was named after the Brilliant Glass factory that once was located in the town. The population was 1,317 as of the 2020 census. It is part of the Weirton–Steubenville metropolitan area. Brilliant was formerly incorporated as a village, but it disincorporated on November 24, 1993.