Disquisitive is defined as having a tendency to question or investigate. Its antonyms, on the other hand, would refer to people who are less inquisitive or tend to avoid questioning. Some antonyms that come to mind include incurious, apathetic, uninterested, indifferent, and nonchalant. Incurious individuals lack a desire to know more or to dig deeper into a subject. Apathetic and uninterested individuals are indifferent to learning new things or exploring new ideas. Nonchalant people are calm and relaxed, they are not eagerly curious or inquisitive. With these antonyms in mind, it becomes clear that the opposite of disquisitive is a lack of curiosity and inquisitiveness.