science
Any branch of study related to factual truths and principles. Likewise, it can be used to discover any facts that have not been uncovered yet using current systematic methods such as hypothesizing, observing, experimenting, measuring, and formulating laws to describe these facts.
There are numerous branches of science, and countless tools used to discover and/or prove these facts. Different scientific branches include mathematics, chemistry, astronomy, biology, engineering, medicine, social sciences, and physics, to name a few.