Mies van der Ro·he (m?z? v?n d?r r???, r??, fän, m?s?), Ludwig 1886-1969. German-born American architect considered a founder of the International Style. His steel-frame and glass buildings include the Seagram Building in New York City (1958) and the Chicago Federal Center (1964-1975).Mies?i·an (m??s?-?n) adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.