A watchword is a guiding principle or motto that people use to remind themselves what matters most. If a basketball coach makes “teamwork” the watchword for the season, she's saying that every decision and action should be guided by helping teammates succeed together. When a principal declares “respect” as the school's watchword, it means treating others with dignity should shape how everyone behaves in the hallways, classrooms, and cafeteria.

In the past, soldiers used watchwords as secret passwords to tell friends from enemies in the dark. Guards would challenge anyone approaching by demanding the watchword. Only someone who knew the correct word could pass safely.

Today, a watchword isn't secret at all. It's the opposite: people share it openly because they want everyone to remember what's important. A family might make “curiosity” their watchword for a museum trip, or a soccer team might adopt “persistence” as their watchword before a tough tournament. When you choose a watchword, you're picking one idea to keep at the front of your mind, like a compass pointing the direction you want to go.