An individual who is knowledgeable about the concepts in a particular problem area within the healthcare arena and/or is experienced with using or providing the functionality of that area.
or "subject matter expert" (SME); a person with special knowledge or skills in a particular area; a person extremely familiar with a given group of users and their work habits (because they belong to the group). A truck driver is an expert in trucking and the needs truckers have for the types of systems that truckers might use, such as delivery or inventory systems. A manager may be a domain expert for project management systems. An accountant is a domain expert for accounting systems. Programmers and user interface designers need to interview domain experts and work with domain experts in the design of systems for the expert's field.
A person who has expertise in a specific problem domain.
A specialist who possesses knowledge and/or expertise about a particular domain, that is, a source of expertise for developing a knowledge base for use by an expert system.
A domain expert or subject matter expert (SME) is a person with special knowledge or skills in a particular area. Domain experts are individuals who are both knowledgeable and extremely experienced with application domains http://nas.cl.uh.edu/helm/swen5534/Do_Ans/tsld002.htm. Dealing primarily with Knowledge-Based Systems (KBS) domain experts are responsible for maintaining, testing, and enhancing the corporate memory sector of the KBS systems.