Antonyms for the word "pre-condition" would include "post-condition," which refers to a condition that occurs after something else has happened. Another antonym could be "unconditioned," meaning there are no requirements or limitations set in place. "Optional" would also be an antonym for "pre-condition," implying that something is not mandatory or necessary for a particular outcome. "Voluntary" is another antonym, indicating that a decision is made without any external pressure or obligation. Ultimately, while various antonyms exist for "pre-condition," they all imply a lack of constraints, requirements, or input that is necessary or expected.