Scaling means that a small piece of an object looks a lot like the larger object it came from. You can see this in the Mandelbrot Set. The small sets around the edge of the large Mandelbrot looks like the fractal it came from.
A twig on a branch looks like the branch which in turns looks like the tree. Clouds, ferns and coastlines are all good examples of scaling. Below is my art showing scaling. The small modules of the broccoflower look like the larger modules which looks like the larger portion itself.