This paper compares definitions of Islamophobia (IP) and antisemitism (AS) in scholarly publications. The literatures differ in four critical ways. First, scholarship on AS tends to conceptualize it as individual prejudice alone, while that on IP often follows the race/ethnicity literature to incorporate structural and systemic exclusion. Second, scholars of IP racialize Islam while the AS literature roots AS in a pre- Enlightenment religious Christian animosity toward Jews that is active even after the Enlightenment-era shift to a racial frame. Third, even though both AS and IP are treated as global discourses with deep historical roots, scholars of IP assert globality by linking it to European colonialism while scholars of AS, even those who in other contexts speak of Israel as a colonial entity, do not. Fourth, scholars of AS debate the uniqueness of AS while scholars of IP tend to see anti-Muslim activity as intertwined with other axes of exclusion. I combine the insights of both literatures into coding instructions for classifying speech. The instructions highlight how different assumptions affect classification of speech as incendiary, and identifies the definitions individuals use when they evaluate their own and others’ speech. My particular interest is in how definitional differences shape interactions between pro-Palestinian and pro-Israel groups on US campuses. Both accuse the other of IP or AS. In addition to the confusion that can result when one group thinks religious prejudice and another structural exclusion, definitions of AS and IP indirectly locate Jews and Muslims in local class and racial/ethnic hierarchies. Regarding class, IP is represented as having a material base, through the references to colonialism and structure, while AS is represented as lacking such a base, through the focus on prejudice alone. This reflects the task, for Jews, of conceptualizing exclusion under conditions of relative class privilege. Regarding race, IP’s racialization and references to colonialism locate Muslims as non-white. The lack of a counterpart in AS, and the assertion of AS’s uniqueness, separate Jews from nonwhites. It is unclear to what degree an unexamined desire to construct the self as white underlies these choices by AS scholars. However a longstanding Israeli literature on Jews, Orientalism, and white supremacy – which does connect AS and colonialism, and undermines Jewish whiteness by centering Middle Eastern and Ethiopian Jews in the analysis – would make that assertion. These links to race and class suggest that campus debates about Israel, AS, and IP have hidden domestic meanings.