Black Monday
n.β Β«Many have taken to calling the benchmark “Black Monday”βpiggybacking on “Black Friday,” the longtime nickname of the day after Thanksgiving, historically the day when sales pushed money-losing stores into the black.Β» ββWeb merchants gear up for busy βBlack Mondayβ” by Mylene Mangalindan Post-Gazette (Pittsburgh, Pa.) Nov. 21, 2005. (source: Double-Tongued Dictionary)