black sheepn.1. A sheep with black fleece.2. One who is considered disreputable or disgraceful by his or her relatives or associates.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.black sheep n a person who is regarded as a disgrace or failure by his family or peer group Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014black? sheep? n. a person who causes shame or embarrassment because of deviation from the accepted standards of his or her group. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.black sheepSomeone who brings disgrace, especially to a family; from the idea that most sheep are white and a black one would be both conspicuous and undesirable.Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited