n.

1. 微明；薄暮；微光[U]
2. 黃昏；黎明[U]
   These animals begin the night's hunt at twilight.

   這些動物在黃昏時分開始一夜的覓食。

3. 衰退期；（人的）暮年，晚期[the S]
   The old man is in the twilight of his career.

   這老人已經進入了他生涯的晚期。

4. 朦朧狀態；模糊狀態[S]
   For three days the patient lay in a twilight of fever.

   病人發燒整整三天，一直迷迷糊糊。

a.

1. 曙暮光的；微明的；昏暗的
2. 衰落時期的；暮年的，晚期的
   The old man spent most of his twilight years working on his autobiography.

   老人暮年的大部分時間都在寫他的自傳。

n.

1. the soft glowing light from the sky when the sun is below the horizon, caused by the reflection of the sun's rays by the atmosphere.
2. a period or state of obscurity or gradual decline:
   the twilight of his career.