Presentiveness is defined as the state or quality of being present or in attendance. The antonyms for the word "presentiveness" would therefore be words that describe the opposite condition, such as absence, nonexistence, non-attendance, or nonappearance. Other antonyms might include words like negation, nonpresence, non-being, or non-occurrence. These terms all imply the lack of a physical, tangible presence or the absence of something that should be there but isn't. In the context of human interactions, the antonyms of presentiveness might be words like aloofness, detachment, unavailability, or remoteness, suggesting emotional or psychological disconnection rather than physical absence.