n.

1. 巨大，廣大[U]
2. 重大，重要[U]
   No one comprehended the magnitude of the problem then.

   當時無人認識到這一問題的嚴重性。

3. 量；大小；強度；音量[U]
   It is difficult to imagine the magnitude of the universe.

   宇宙的廣大很難想像。

4. 【天】星等（指星的亮度）[C]
   a star of the second magnitude

   第二星等的一顆星

5. 【地】震級[C]
   A giant earthquake registering 9.1 magnitude hit California, causing the death of several thousand people.

   一個震度達9.1級的大地震襲擊加州， 造成數千人的死亡。

n.

1. great size, extent, or importance.
2. size:
   electorates of less than average magnitude.
3. Astronomy  the brightness of a star, as represented by a number on a logarithmic scale.