"Dreggiest" refers to the lowest quality or most undesirable state of something. Some antonyms for "dreggiest" could include words like "best," "highest quality," "premier," "optimal," or "superior." These words suggest a state of excellence or superiority, in contrast to the inferiority or lowliness implied by "dreggiest." Other possible antonyms for "dreggiest" might depend on context. For example, if discussing levels of cleanliness, antonyms could include "cleanest," "tidiest," or "most hygienic." Similarly, antonyms for "dreggiest" in the context of morals or values might include words like "virtuous," "upstanding," or "ethical.