The antonyms for the phrase "most white hot" are numerous, as there are varying degrees of temperature from freezing to boiling or scorching temperatures. Some possible antonyms for this phrase include "cold," "chilly," "frigid," "cool," "tepid," "lukewarm," "warm," "hot," and "boiling." The opposite of "most white hot" may depend on the context of where it is used, such as in the context of a stove-top burner, a light bulb, or the sun. Nevertheless, the antonyms for this phrase all depict some form of a decrease in temperature or intensity from the highest possible level.