Charles A. Ferguson

Charles A. Ferguson was an American linguist who in a widely cited 1959 paper coined the term diglossia in its now-standard linguistic sense, describing a society in which two distinct varieties of the same language are used in strict complementary distribution, a formal high variety reserved for writing, education and formal speech, and a colloquial low variety used in everyday conversation, drawing on cases such as Arabic, Modern Greek, Swiss German and Haitian Creole. Ferguson also carried out influential early research on what he called baby talk registers, the simplified speech adults commonly use when addressing young children, and on other special registers adapted to particular audiences or situations, contributing to the study of linguistic register more generally. Ferguson served as founding director of the Center for Applied Linguistics in Washington, D.C., and later as a professor at Stanford University, where he helped shape the study of language universals and language typology alongside his sociolinguistic research, mentoring a wide circle of students who went on to shape sociolinguistics as a discipline.