The corpus of descriptive terminology associated with achievement testing has expanded considerably in recent years, in large part due to the heightened interest in absolute and/or direct metrics for interpreting test performance plus the development of more rigorous strategies for specifying test content. Widely prevalent disagreement about terminology reflects a lack of conceptual clarification and may inhibit the development of theory and practice. Distinctions commonly made between criterion referenced and norm referenced tests turn out to be inaccurate, since it appears that both content and norm referenced interpretations can apply to scores on any type of achievement test. Rather, the particular manner in which a given test can and should be interpreted turns out to be a function of the mode by which test content is specified and the function for which the test is to be used. All approaches to the interpretation of achievement test scores are classified as either domain referenced or norm referenced, with reference to a criterion or standard viewed as a special case of the former. Finally, it is argued that normative interpretations can and in many instances should be made of scores which are referenced directly to content, including mastery scores. (Author/BW)