nalorphine (?næl??fi?n) n (Pharmacology) an anti-narcotic drug used esp to counteract the effects of morphine poisoningCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014nal?or?phine (?næl ?r?fin, næl??r fin) n. a narcotic antagonist, C19H21NO3, chemically related to morphine, used to counteract overdose and to diagnose addiction. [1950?55; N-al(lyln)or(mor)phine] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.