a.

1. 致命的，致死的；毒性的
   This is a deadly poison.

   这是一种致命的毒药。

2. 不共戴天的；殊死的[B]
   He is my deadly enemy.

   他是我的死敌。

3. 死一般的[B]
   There was deadly silence in the valley.

   山谷里死一般的沉寂。

4. 【口】非常的，极度的[B]
   deadly dullness

   极度的沉闷

5. 【口】非常无聊的，令人厌烦的
   Our maths classes are pretty deadly.

   我们的数学课非常枯燥。

ad.

1. 死一般地
   His face was deadly pale.

   他的脸死一般地苍白。

2. 非常，极度地
   The air was deadly cold.

   空气极度寒冷。

adj.

1. causing or able to cause death.
   ▸filled with hate.
2. extremely accurate or effective.
3. informal extremely boring.
4. complete:
   she was in deadly earnest.

adv.

1. in a way that resembles or suggests death.
2. extremely.