1. (常指在生理上，有时也指在精神上)生病的，有病的
If you are sick, you are ill. Sick usually means physically ill, but it can sometimes be used to mean mentally ill.
e.g. He's very sick. He needs medication...
他病得很厉害，需要药物治疗。
e.g. She found herself with two small children, a sick husband, and no money...
她发觉自己有两个年幼的孩子和一个有病在身的丈夫，却没钱养活他们。
2. 呕吐的;恶心的;想吐的
If you are sick, the food that you have eaten comes up from your stomach and out of your mouth. If you feel sick, you feel as if you are going to be sick.
e.g. She got up and was sick in the handbasin...
她起身在洗手池里吐了起来。
e.g. The very thought of food made him feel sick...
一想到食物他就恶心。
3. 呕吐物
Sick is vomit.
4. 厌倦的;厌烦的;厌恶的
If you say that you are sick of something or sick and tired of it, you are emphasizing that you are very annoyed by it and want it to stop.
sick的近义词
e.g. I am sick and tired of hearing all these people moaning...
我厌倦了听这些人大发牢骚。
e.g. Most people here are sick of violence.
这儿的大多数人都厌恶暴力。
5. (笑话、故事等)令人毛骨悚然的，病态的，不健康的
If you describe something such as a joke or story as sick, you mean that it deals with death or suffering in an unpleasantly humorous way.
sick是什么意思
e.g. ...a sick joke about a cat...
关于猫的一则令人毛骨悚然的笑话
e.g. That's really sick.
那真够吓人的。