We do that incredibly often just to refer to only one part of an incredibly broad concept of "science." Sometimes they get unique terms like "physics" or "chemistry," but not always. This is not a rule that can accurately be applied to all terms matching the pattern "____ science."
What we call science is short for natural science. Science just comes from the Latin word for knowledge. Different disciplines have different ways of building knowledge. That doesn't necessarily make one better or worse.
