The word "over-riding" means to prioritize, dominate or control. The antonyms for "over-riding" include "secondary", "subordinate" and "lesser". These words indicate that something is of less importance or less influential. Another antonym for "over-riding" is "negligible", which means insignificant or trivial. Another antonym for "over-riding" is "underlying", which implies that something is underlying or foundational to something else. Overall, these antonyms for "over-riding" suggest that something is not dominant or prioritized and is of lesser significance or importance.