Using gender analysis helps to see the gender biases in the concept of ‘terrorism’ that are at the apex of its definitional concerns, political problems, and moral ambiguities. The first section of this chapter examines the definitional problem of terrorism, not just for inconsistencies but also for how what or who is included (and excluded) in common definitions and how these inclusions/exclusions are gendered. In the second section, we problematize terrorism by looking for its gendered implications. The next section points out one of the important elements of using gender analysis to theorize terrorism: understanding how people identified as terrorists are gendered in media and scholarly discussions of their actions. The final section discusses genderings in counterterrorism theory and practice.