In considering students' thinking, the phenomenographic tradition has paid considerable attention to conceptions of various phenomena within the context of learning. However, this research has not explicitly examined the relation between words used and their meaning in the processes of understanding and learning. The present study concerns the character of the relationships between verbal expressions and thoughts about phenomena referred to. In order to understand these relationships more fully, an empirical study was carried out. Twenty-seven students from two institutes of higher education, a college of health science and a college of education, participated. Qualitative interviews were used to both stimulate students' thinking about the conceptions they expressed of a particular problem and to document their thinking. Contextual analysis was used to examine this data. The results of the analysis are presented in three related descriptive categories. The categories represent three different aspects of relationships between words used and thoughts about phenomena referred to and three different developments of these relationships. Finally, conclusions are drawn and are discussed in relation to research on understanding and learning and two major traditions in the philosophy of language.