A hazy or dim state of consciousness; being only partially conscious or feeling groggy/dazed.
高熱で意識朦朧として、何を言われても返事ができなかった。
With a high fever I was groggy and couldn't respond no matter what was said to me.
事故で頭を打ち、しばらく意識朦朧の状態が続いた。
He hit his head in the accident and remained dazed for a while.