Benedict of Nur·si·a (nûr?sh?-?, -sh?), Saint ad 480?-547? Italian monk who as founder of the Benedictine order (c. 529) is considered the patriarch of Western monasticism.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.