mo·raine (m?-r?n?)n. An accumulation of boulders, stones, or other debris carried and deposited by a glacier.[French, from French dialectal morena, mound of earth, from Provençal morre, muzzle, from Vulgar Latin *murrum.]mo·rain?al, mo·rain?ic 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.moraine (m??re?n) n (Physical Geography) a mass of debris, carried by glaciers and forming ridges and mounds when deposited[C18: from French, from Savoy dialect morena, of obscure origin] mo?rainal, mo?rainic adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014mo?raine (m??re?n) n. 1. a ridge, mound, or irregular mass of unstratified glacial drift, chiefly boulders, gravel, sand, and clay. 2. a deposit of such material left on the ground by a glacier. [1780?90;