Background: Previous research has found that bullying is often defined differently by students, staff and researchers, leading researchers to call for a more consistent use of the term in practice to enable better intervention and measurement. However, little is known about the consequences of a more consistent use of the term in school. Purpose: The article examines the consequences of schools adopting an exact definition of bullying. Sample: Twenty Norwegian primary and lower secondary schools were selected from a survey (n = 455). The schools were characterised by a strong culture of bullying prevention, and their staff and students knew and used the same authoritative bullying definition. Four schools were then selected for closer ethnographic study. Design and methods: Interviews were conducted with students, teachers, support staff and school management. The interviews were analysed qualitatively, using a grounded theory approach. Results: For school staff, the term 'bullying' was construed as rigid and possessing an inherent power that is manifested through the way the term controls adults' actions. Teachers viewed students' use of the term as too wide. They emphasised the need to teach students the established definition, as students' overuse of the term may lead to the word's diminishing impact for those who are in real need of help. Nevertheless, many of the educators stated that few students report bullying. Both school staff and students displayed a sense of certainty when identifying what counts as bullying. Students' recognition of the power of the word was apparent in the way they used the term as a tool for social positioning. Conclusions: By way of the status of a bullying definition as an established, researchbased definition, it gains a potent power for management, teachers and students. Its power Page 3 of 33 lies in the fact that the use of the term gives rights and responsibilities, determines guilt, and confers blame and status. Unwanted effects of a strict control of the bullying term may involve the risk of missing cases and the risk that students use the term as a tool in the power relations between the students themselves.