The antonyms of the word "most smoldering" can be used to describe something that is cold, calm, or extinguished. Words such as frozen, extinguished, inactive, dormant, and peaceful are antonyms for smoldering. Frozen depicts something that is completely devoid of heat, extinguished represents something that is no longer burning, and dormant means that something is in a state of rest or inactivity, while peaceful suggests a sense of calm and tranquility. These antonyms can be used to add contrast to the word "smoldering," which can evoke a sense of heat, danger, and intensity.