Black Monday

1. The first Monday after the holidays; — so called by English schoolboys.
2. Easter Monday, so called from the severity of that day in 1360, which was so unusual that many of Edward III.’s soldiers, then before Paris, died from the cold.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.