Takeoff is the moment when an aircraft leaves the ground and begins to fly. During takeoff, a plane accelerates down the runway, gaining speed until its wings generate enough lift to pull it into the air. Pilots carefully calculate how much runway they need based on the plane's weight, the weather, and other factors.

The Wright brothers achieved the first powered takeoff in 1903, staying airborne for just 12 seconds. Today, massive passenger jets weighing hundreds of tons perform takeoffs thousands of times a day around the world.

The word also describes any rapid beginning or sudden increase. A rocket's takeoff is explosive and dramatic. When a business experiences takeoff, it suddenly starts growing quickly after a slow start. A runner might take off from the starting blocks, or a student's grades might take off after they develop better study habits. In each case, takeoff captures that crucial moment when something transitions from stillness or slow progress into rapid forward motion.