a.

1. 壞的，不好的；拙劣的；令人不悅的
   The weather was really bad.

   天氣真糟。

2. 不健全的；有病的；疼痛的
   I felt bad all day.

   我整天覺得不舒服。

3. 有害的[（+for）]
   Reading in a dim light is bad for the eyes.

   在暗淡的光線下看書有損視力。

4. 嚴重的；厲害的
   She's got a bad headache.

   她頭痛得厲害。

5. （食物）腐壞的；腐爛的
   The meat has gone bad.

   這肉已壞了。

6. 不適合的；不適當的
   They arrived at a bad time.

   他們來得不是時候。

7. 【口】遺憾的；後悔的[（+about/at）][+（that）]
   I feel bad about losing your dictionary.

   我很抱歉把你的字典丟失了。

8. 好極了的；棒極了的

n.

1. 不好的東西或情形[the S]
   You must learn to take the bad with the good.

   人必須學會好壞都能承受。

ad.

1. 【美】【口】壞
   Alison sings bad.

   艾莉森唱得很糟。

2. 【美】【口】很，非常

adj.

1. of poor quality or a low standard.
   ▸ (often bad at) not able to do a particular thing well.
   ▸inappropriate.
2. unwelcome or unpleasant.
   ▸severe or serious.
   ▸ (bad for) harmful to.
3. offending moral standards or accepted conventions.
4. injured, ill, or diseased.
5. (of food) decayed.
6. guilty; ashamed.
7. (badder, baddest)
   informal, chiefly N. Amer. good; excellent.