Guy Deutscher (Hebrew: גיא דויטשר; born 1969, Tel Aviv) is an Israeli linguist.
He is an Honorary Research Fellow at the University of Manchester and was a professor in the Department of Languages and Cultures of Ancient Mesopotamia at the University of Leiden in the Netherlands. He received an undergraduate degree in mathematics at University of Cambridge, before going on to earn a Ph.D. in linguistics there. After that he undertook research in Historical Linguistics at St John's College, Cambridge. He has written three books: Syntactic Change in Akkadian (2000), The Unfolding of Language (2005), and Through the Language Glass (Heinemann, 2010. ISBN 978-0-434-01690-7).
Guy is the father of Alma Deutscher, the very young composer and musician.
Awards and honors