Sub-dual means the act of subduing or bringing something or someone under control. Some antonyms, or words with the opposite meaning, for sub-dual include liberation, emancipation and release. These words denote a sense of freedom, escape or lack of control, rather than restraint or submission. Other antonyms could include empower, enable or embolden, as these words suggest a sense of strength, assertiveness, and control - opposite to the idea of sub-dual. It is necessary to consider the context in which the opposite word is being used, as sometimes different words can be used to express nuances of meaning.