It stands for an interesting system that suggests the daylight entering through a skylight.
This modular design provides an architectural dimension to the object and is adapted to spaces of varying size and geometry. The system consists of four modules of different sizes and depths that combine in unlimited ways and orientations. The modules are electrically connected together.
Here is a description from Vibia producers:
Like the skyline of a great city… The modules of the Link lighting system allow you to create silhouettes and volumes on the ceiling to suit every room and every location.