1.Diligent inquiry or examination in seeking facts or principles; laborious or continued search after truth; as, researches of human wisdom; to research a topic in the library; medical research. "The dearest interests of parties have frequently been staked on the results of the researches of antiquaries."
2.Systematic observation of phenomena for the purpose of learning new facts or testing the application of theories to known facts; also called scientific research. This is the research part of the phrase "research and development" (R&D). Note: The distinctive characteristic of scientific research is the maintenance of records and careful control or observation of conditions under which the phenomena are studied so that others will be able to reproduce the observations. When the person conducting the research varies the conditions beforehand in order to test directly the effects of changing conditions on the results of the observation, such investigation is called experimental research or experimentation or experimental science; it is often conducted in a laboratory. If the investigation is conducted with a view to obtaining information directly useful in producing objects with commercial or practical utility, the research is called applied research. Investigation conducted for the primary purpose of discovering new facts about natural phenomena, or to elaborate or test theories about natural phenomena, is called basic research or fundamental research. Research in fields such as astronomy, in which the phenomena to be observed cannot be controlled by the experimenter, is called observational research. Epidemiological research is a type of observational research in which the researcher applies statistical methods to analyse patterns of occurrence of disease and its association with other phenomena within a population, with a view to understanding the origins or mode of transmission of the disease.