This article conceptualises a combined autism and ADHD (AuDHD) diagnosis as a residual category not formally represented in diagnostic systems, addressing a critical gap in neurodiversity research. Using Interpretative Phenomenological Analysis of email interviews with six women diagnosed in adulthood, it examines the ambivalence arising from inhabiting this liminal diagnostic space. Residuality generates conflicting feelings about autism, ADHD, and the self, resulting in fragmented identities…