Background: It is a peculiar fact that the deadliest psychiatric disturbance – suicidality – cannot be formally diagnosed. Suicidal behavior disorder (SBD), a condition for further study in the DSM-5, is the field’s first attempt to capture suicidality in a diagnosis. Aims: To provoke discussion about the standing of suicidality as a diagnosable psychiatric condition. Method: I present pragmatic and conceptual rationales for why a diagnosis of suicidality is clinically useful but conclude that SBD does little to aid clinicians in assessing suicidality’s symptoms, planning treatment, or monitoring progress. Results: To improve the clinical utility of SBD, I re-conceptualize it from the vantage point of descriptive psychiatry. I hypothesize that this revised SBD is an independent, episodic, and frequently co-occurring condition and propose new cognitive, affective, and behavioral criteria that more completely capture the phenomenology of suicidality. Conclusion: The revised SBD is a starting place for dialogue about whether a clinically significant presentation of suicidality is a mental illness and, if it is, what its defining features should be.