burden of proofn. Law The duty of presenting a certain amount of evidence in order to meet the legal requirements for establishing the entitlement of the party in a case to the outcome sought.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.burden of proof n (Law) law the obligation, in criminal cases resting initially on the prosecution, to provide evidence that will convince the court or jury of the truth of one’s contention Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014bur?den of proof? n. the obligation to offer credible evidence in a court of law in support of a contention or accusation. [1585?95] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.