ABSTRACT Student engagement is currently a topical aspect of teaching and learning due to its influence on students’ learning experiences and outcomes. The literature delineates student engagement as a malleable construct, involving a student’s behaviour, emotions, and cognitions, all of which are influenced by the learning context, and more specifically, by the teacher. Indeed, teachers are pivotal in fostering engagement in the classroom, and their pedagogical decisions can significantly impact on a student’s engagement. The aim of this study was to investigate secondary teachers’ understandings of student engagement in relation to three dimensions (behavioural, emotional, and cognitive engagement) using an online questionnaire (n = 223). The study findings indicated that teachers describe an engaged student and define student engagement in different ways. Some teachers described student engagement as including only behavioural or emotional or cognitive dimensions, others described it as involving more than one dimension, while yet others defined engagement as including all three dimensions. This research supports the view that teachers’ conceptual understandings may play a key role in teachers’ prioritisation of strategies to foster engagement in their classrooms. These findings contribute new insights to existing research, prompting a reimagining of effective approaches to support student engagement in the classroom.