The word "most festering" refers to something that is rotting, decaying or deteriorating. Antonyms for "most festering" include "healthy", "fresh", "clean" and "wholesome". These words describe things that are in good condition, free from decay or disease. Another antonym for "most festering" is "pure", which suggests cleanliness and freedom from impurities. While "most festering" connotes something unpleasant and unattractive, its antonyms convey positivity and beauty. In summary, the antonyms for "most festering" describe the opposite of decay and deterioration, representing beauty, cleanliness and good health.