The antonyms for the word "most propagating" are certain to depend on the context of its usage. In general, antonyms for "propagating" might include words that imply the opposite, such as "reducing," "obstructing," "preventing," "stifling," or "stagnating." Depending on the precise meaning of "most propagating," appropriate antonyms might differ. For example, if "most propagating" were being used to describe growth in a population or the spread of a disease, antonyms could include "declining," "diminishing," or "subsiding." If referring to the dissemination of ideas or propaganda, synonyms for "propagating" could be "reducing," "opposing," or "subverting.