If something is sparsest, there is very little of it and things are far apart.
Sparsest can make people think of emptiness, loneliness, or not enough of something.
Examples:
The desert is the sparsest place I know.
The sparsest forest has only a few trees.
In the sparsest room, there is only one chair.
The sparsest lunch I ever had was just a small sandwich.
The sparsest stars are in the daytime sky.
The sparsest library has only one book.