A pillbox is a small container designed to hold pills or medicine, usually with separate compartments for organizing doses. Many pillboxes have sections labeled with days of the week, helping people remember whether they've taken their daily vitamins or medication. Your grandmother might use one to keep track of her heart medicine, or an athlete might use one to organize supplements for training days.

The word also refers to a type of small, round hat with a flat top and no brim, popular in the 1960s. First Lady Jacqueline Kennedy made pillbox hats famous, and they got their name because they resembled the small round containers used to hold pills.

In military history, a pillbox was a small concrete shelter with narrow openings for guns, built to protect soldiers during battle. These bunkers were called pillboxes because their low, boxy shape reminded people of the medicine containers. You can still see old military pillboxes along the coasts of Europe from World War II, now covered in moss and weeds but once crucial defensive positions.