Many websites claim that the phrase Black Friday, referring to the shopping bonanza after Thanksgiving, is so named because it's the day when the stores' ledgers go from in the red to in the black. This is a linguistic myth: the term actually became popularized by the Philadelphia Police Department in the 1960s, when they used the name to describe the shopping pandemonium in downtown stores. Here, "black" was used pejoratively (like how Black Tuesday and Black Thursday described the crashes in 1929), and the moniker was originally unpopular with retailers. However, they soon realized that it wasn't going anywhere, so they reinvented the term in the 1980s to have more positive connotations, using it in advertisements and creating the "red to black" myth.
Hello! I'm Adam Aleksic, a senior studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy trivia, politics, vexillology, geography, board games, conlanging, art history, and law.