"Most bottom-rung" is a phrase used to describe the lowest level or position in a hierarchy. Its antonyms would be "highest echelon," "top tier," or "uppermost rung." These adjectives signify a level of excellence, superiority, or achievement. In contrast, antonyms of "most bottom-rung" convey a sense of prestige and exclusivity. For example, a CEO would be considered part of the top tier, while an entry-level employee would be part of the bottom-rung. The antonyms of "most bottom-rung" can represent success, respect, and admiration, which are qualities that many people strive for in their careers and personal lives.