(ˈsãʊ̃ tʊˈmeɪ) n. 1. an island in W Africa, off the W coast of Gabon: the larger component of the republic of São Tomé and Príncipe. 106,900; 326 sq. mi. (847 sq. km). 2. a city on this island: capital of the republic. 35,000. São` To•me′an,n., adj.