Irritability and behavioral symptom dimensions of oppositional defiant disorder (ODD) in youth exhibit differential associations with adult psychopathology. Recently, researchers have begun to examine ODD in adults, with evidence that symptoms persist into adulthood and continue to cause impairment above and beyond other types of psychopathology. Based on this emerging literature, there is a need to understand how ODD symptoms in adulthood relate to novel frameworks for characterizing adult psychopathology. Three-hundred and four young adult college students completed measures of ODD symptoms, DSM-5 pathological personality traits, ADHD, depression, and anxiety. Poisson regression was used to predict ODD severity score from the five DSM-5 personality traits, while controlling for sex, race, and comorbid psychopathology. Structural equation modeling was used to test competing models of ODD structure, and then to examine ODD dimensions and their specific associations with other psychopathology and the DSM-5 traits. Results show that ODD severity was positively associated with negative affectivity, antagonism, and disinhibition, and negatively associated with psychoticism. The two-factor model, with correlated irritability and behavioral dimensions, fit better than the unidimensional model. Irritability was uniquely associated with anxiety, depression, negative affectivity, and detachment, while the behavioral dimension was uniquely associated with ADHD, antagonism, and disinhibition. These analyses provide evidence that symptoms of ODD in young adults are associated with DSM-5 pathological personality traits above and beyond other psychopathology. These findings provide a framework for future studies and clinical consideration of ODD among adults.