The field of cybersecurity is predicated on the existence of humans who deliberately attack computer systems. In other words, without cyber adversaries, there is no cybersecurity. Therefore, adversarial thinking, which is the study of cyber adversaries, is central to a cybersecurity education.  However, the learning outcomes associated with adversarial thinking are not well-defined, making it difficult for cybersecurity educators to confidently instruct students in this crucial area.  This presentation aims to advance cybersecurity education by rigorously defining what it means to “think like a hacker.” The proposed definition highlights the primary learning outcomes associated with adversarial thinking, and it will help educators see more clearly the big picture of a cybersecurity education.  This presentation will also promote the CLARK curriculum repository where cybersecurity educators can find materials to help develop the adversarial thinking abilities of their students.