ring·fort (r?ng?fôrt?)n. An ancient or medieval settlement or farmstead fortified with a circular bank, ditch, or stone wall, situated usually on a hill or promontory in northern Europe, and especially in Ireland. 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.