Antonyms for the phrase "most low-down-and-dirty" may include words like honorable, ethical, righteous, decent, virtuous, respectful, noble, and principled. When we talk about someone or something being low-down-and-dirty, we often refer to actions or behaviors that are morally corrupt or dishonest. Thus, the opposite of this can be anything that embodies moral rectitude, high ethical standards, and commendable conduct. The antonyms mentioned here highlight the positive aspects that are valued in society and represent a higher standard of human behavior, which is in stark contrast to the disgraceful traits and actions described by the original term.