1. Tell that joker to stop using my parking space.
    告诉那个家伙不要占用我的停车场。

1. 爱开玩笑的人；逗趣的人
    Someone who is a joker likes making jokes or doing amusing things.

    e.g. He is, by nature, a joker, a witty man with a sense of fun.
           他天性是个爱开玩笑的人，说话诙谐，很有幽默感。

2. （纸牌中的）百搭牌，王牌
    The joker in a pack of playing cards is the card which does not belong to any of the four suits.

3. 愚蠢的人；举止危险的人；小丑
    You can call someone a joker if you think they are behaving in a stupid or dangerous way.

    e.g. Keep your eye on these jokers, you never know what they will come up with.
           留神那些活宝，你永远也不知道他们会想出什么样的主意。

4. 与众不同的人（或事物）；难以捉摸的人（或事物）
    If you describe someone or something as the joker in the pack, you mean that they are different from the other people or things in their group, and can be unpredictable.

1. a playing card that is usually printed with a picture of a jester

2. an inconspicuous clause in a document or bill that affects its meaning in a way that is not immediately apparent

    e.g. when I demanded my money he showed me the joker in the contract

3. a person who enjoys telling or playing jokes

    Synonym: jokester

4. a person who does something thoughtless or annoying

    e.g. some joker is blocking the driveway

    Synonym: turkey