The antonyms for the word "most underestimated" are appreciated, overrated, well-regarded, respected, and esteemed. When you appreciate someone or something, you acknowledge and value their worth, instead of underestimating their capabilities. Similarly, when something is overrated, it is given more credit than it deserves, rather than being underestimated. Something that is well-regarded is held in high esteem, and respected by others for its worth, which is the opposite of something that is underestimated. Esteemed is another antonym for most underestimated, which denotes the high regard and respect that is given to a person or thing, which is entirely different than being underestimated.