How the term urban and other terms related to it are defined can enhance the efficiency of research on urban education issues. A review of urban and related word uses reveals considerable variety in definitions. Since the aim of much research is to derive useful generalizations applicable to other similar groups, it is important to define the characteristics that accompany the term urban. The following questions would help to define this key term: (1) Why is this study considered to be urban research? (2) For the purposes of this study, what are significant characteristics of the educational establishment? (3) What are significant characteristics of the urban environment and of other settings designated by such terms as rural, suburban, and the like? (4) What explanation should be offered to readers so as to optimize their use of the research report? When investigators begin by defining in operational terms the aspect of the education system that will be viewed as the outcome variable, then features of the urban environment that hypothetically contribute to the outcome variable are also defined operationally. This combination of education-aspect and urban-environment features becomes the definition of urban for the purposes of the particular project. Cited are four references. (JB)