Unrestrained, as the word suggests, refers to a state where there are no restrictions or limitations. Its antonyms, therefore, are words that describe the presence of restraint or control. Some antonyms for unrestrained include restricted, confined, controlled, curbed, limited, regulated, and moderated. Restrained refers to holding back or limiting oneself from indulging in something excessively. Confined implies restrictions or limitations due to boundaries or confinement in space. Controlled suggests a state where actions are managed or regulated. In summary, the antonyms for the word "unrestrained" describe various forms of limitations, control, or reduction.