bad hair daya disagreeable day in which one?s hair looks weird and one feels stupid lookingAbused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embreebad hair day n 1. a day on which one’s hair is untidy and unmanageable 2. a day of mishaps and general irritation Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014bad? hair? day` n. a disagreeable or unpleasant day, esp. when one feels unattractive. [1990?95] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.