sub·duc·tion (s?b-d?k?sh?n)n. A geologic process in which one edge of one crustal plate is forced below the edge of another.[French, from Latin subductus, past participle of subd?cere, to draw away from below : sub-, sub- + d?cere, to lead; see deuk- in Indo-European roots.]sub·duct? v.sub·duc?tal (-t?l) 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.subduction (s?b?d?k??n) n1. (Physiology) the act of subducting, esp of turning the eye downwards2. (Geological Science) geology the process of one tectonic plate sliding under another, resulting in tensions and faulting in the earth’s crust, with earthquakes and volcanic eruptionsCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014sub?duc?tion (s?b?d?k ??n) n. the process by which collision of the earth’s crustal plates results in one plate’s being drawn down or overridden by another, localized along the juncture (subduc?tion zone`) of two plates. [1965?70;