What does the Aditya-L1 observatory's definition of L-1 mean?

The first Indian space observatory, Aditya-L1, is orbiting the Sun in a halo around the first Sun-Earth Lagrangian point (L1), which is about 1.5 million kilometers from the planet. On September 3, 5, and 10, the first, second, and third earth-bound manoeuvres, respectively, were completed successfully. The maneuvers are being carried out during the spacecraft's 16-day orbit of the Earth, during which time it will pick up speed in preparation for its subsequent trip to L1.