Day that opens the Christmas shopping season with major reductions in many retail stores. The term alludes to the fact that businesses make enough sales (profit) to get them «out of the red» (losses) and into the black (profit) in reference to the colour of ink formerly used by accountants.
It is a day after Thanksgiving Day, which is celebrated on the fourth Thursday of November. Some black friday sales are now starting the day or night before. Black friday was also a term given to the first stock market crashes, specifically the gold market collapse on September 24, 1869