Research in science education often has the goal of enhancing student success, yet there is a dearth of literature related to how students define success for themselves. In this study, we explored how 10 life science graduate students defined the term "success," as well as their experiences related to success. Using interpretive phenomenological analysis, we discovered that students had definitions of success that included multiple components and that students' definitions varied widely and were influenced by a number of factors. Students described challenges to their success--including lack of departmental support--as well as supports to their success--like caring relationships with others. Students felt guilty about having definitions that were not wholly academic, and their perceived misalignments between these definitions and those of their advisors or department generated negative feelings and a low sense of belonging. Finally, students described how their definitions of success had changed since entering graduate school. Our results suggest that student definitions of success are complex and that, as researchers and programs seek to enhance student success, they should attend to the diverse perspectives that students have about this concept; this may be an integral strategy to address students' well-being within academia.