Domestic abuse is a worldwide public health issue with long-term health and social consequences. Nurses play a key role in recognizing and responding to domestic abuse. Yet there is considerable evidence that their responses are often inappropriate and unhelpful, such as trivializing or ignoring the abuse. Empirical studies have identified several reasons why nurses' responses are sometimes wanting. These include organizational constraints, e.g. lack of time and privacy; and interpersonal factors such as fear of offending women and lack of confidence. We propose, however, that these factors present only a partial explanation. Drawing on the work of Julia Kristeva, we suggest that alternative understandings may be derived through applying the concept of abjection. Abjection is a psychological defence against any threat (the abject) to the clean and proper self that results in rejection of the abject. Using examples from our own domestic abuse research, we contend that exposure of nurses to the horror of domestic abuse evokes a state of abjection. Domestic abuse (the abject) transgresses established social boundaries of clean and proper. Thus when exposed to patients' and clients' experiences of it, some nurses subconsciously reject domestic abuse as a possibility (abjection). They do this to protect themselves from the horror of the act, but in so doing, render themselves unable to formulate appropriate responses. Rather than understanding the practice of some nurses as wilfully neglectful or ignorant, we argue that through a state of abjection, they are powerless to act. This does not refute existing evidence about nurses' responses to domestic abuse. Rather, as a relatively unknown concept in nursing, abjection provides an additional explanatory layer that accounts for why some nurses respond the way they do. Crucially, it elucidates the need for nurses to be supported emotionally when faced with the transgressive practice of abuse.