al·ter·a·tion (ôl?t?-r??sh?n)n.1. The act or procedure of altering.2. The condition resulting from altering; modification.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.alteration (???lt??re???n) n1. an adjustment, change, or modification2. the act of altering or state of being alteredCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014al?ter?a?tion (??l t??re? ??n) n. 1. the act of altering or the state of being altered. 2. a change; modification. [1350?1400] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.