The term "twilight world" refers to a state of ambiguity, uncertainty, or blurred reality. Antonyms for this phrase would, therefore, describe things that are clear, certain, or well-defined. Antonyms might include ideas such as "clarity," "certainty," "truth," or "reality." Opposite terms could also include "daytime world," which would indicate a setting with bright lighting and a clear view of one's surroundings. Another antonym could be "high visibility world," reflecting a situation where there is no confusion or uncertainty. Other potential antonyms for "twilight world" might include words like "lucid," "well-defined," or "unambiguous.