'K' was chosen to stand for a strikeout in baseball because 'S' was already in use

While it may make more sense that the letter ‘S’ denotes a strikeout in baseball, the letter was already in use. Henry Chadwick was a writer in the 1860s with a love of baseball and is largely considered the father of baseball stats keeping. He decided that the letter ‘S’ would be used in baseball as the symbol for ‘sacrifice’, which is when a player bunts the ball in order to let his teammates advance around the bases while he gets knocked out. Since S was taken, Chadwick selected the letter ‘K’ to denote a strike.