1. 吹口哨；用口哨吹出(曲调)
    When you whistle or when you whistle a tune, you make a series of musical notes by forcing your breath out between your lips, or your teeth.

    e.g. He whistled and sang snatches of songs...
           他吹口哨并唱了几段小曲。
    e.g. He was whistling softly to himself...
           他轻声吹着口哨。

2. (吃惊、唤狗、赞叹等时)发出口哨声
    When someone whistles, they make a sound by forcing their breath out between their lips or their teeth. People sometimes whistle when they are surprised or shocked, or to call a dog, or to show that they are impressed.

    e.g. He whistled, surprised but not shocked...
           他吹了声口哨，很是惊讶但没有被吓住。
    e.g. Jenkins whistled through his teeth, impressed at last...
           詹金斯吹了声口哨，最终被打动了。

3. (火车)鸣汽笛；(水开时水壶)发出尖啸声
    If something such as a train or a kettle whistles, it makes a loud, high sound.

whistle的反义词

    e.g. Somewhere a train whistled...
           不知哪里的火车在鸣汽笛。
    e.g. ...the whistling car radio.
           车载收音机的尖啸声

4. (风、子弹等)呼啸而过
    If something such as the wind or a bullet whistles somewhere, it moves there, making a loud, high sound.

    e.g. The wind was whistling through the building...
           风呼啸着穿过大楼。
    e.g. As I stood up a bullet whistled past my back.
           我起身时一颗子弹嗖的一声从我背后擦过。

5. (空气或液流通过狭窄孔洞时发出的)呼啸声;(物体在空气中快速移动时的)呼呼声
    A whistle is a loud sound produced by air or steam being forced through a small opening, or by something moving quickly through the air.

    e.g. Hugh listened to the whistle of a train.
           休听着火车呼啸而过。
    e.g. ...the whistle of the wind.
           呼啸的风声

6. 哨子
    A whistle is a small metal tube which you blow in order to produce a loud sound and attract someone's attention.

    e.g. On the platform, the guard blew his whistle...
           平台上的警卫吹响了哨子。
    e.g. The referee blew his whistle for a penalty.
           裁判鸣哨判罚。

7. 上下班的哨声
    Some factories and other places where people work have a whistle which signals the beginning and the end of the working day.

    e.g. Every night you could hear the whistles of the steel mill.
           每晚你都会听见炼钢厂的下班哨声。

8. 口哨(一种乐器)
    A whistle is a simple musical instrument in the shape of a metal pipe with holes.

9. (尤指向当权者)告发，揭发
    If you blow the whistle on someone, or on something secret or illegal, you tell another person, especially a person in authority, what is happening.

whistle的解释

    e.g. Companies should protect employees who blow the whistle on dishonest workmates and work practices.
           公司应该保护那些检举不诚实的工友及工作行为的员工。

10. 得不到;徒然想得到
      If you say that someone can whistle for a particular thing, you mean that you are not willing or able to give it to them.

      e.g. 'He wants a police escort.' — 'Well, he can whistle for that.'
             “他希望有警卫护送。”——“那他是指望不上了。”

11. 非常清洁
      If you describe something as clean as a whistle, you mean that it is completely clean.

12. 无错的;问心无愧的
      If you describe someone as clean as a whistle, you mean that they are not guilty of having done anything wrong.

      e.g. 'His private life is as clean as a whistle,' says McSmith.
             “他的私生活没有任何污点，”麦克史密斯说。

13. 借吹口哨壮胆;故作镇定
      If you say that someone is whistling in the dark, you mean that they are trying to remain brave and convince themselves that the situation is not as bad as it seems.

      e.g. Then I waited, trying not to feel as if I were whistling in the dark, but I experienced no easing of my fear and anxiety.
             之后我开始等待，并竭力保持镇定，可是恐惧和焦虑却丝毫没有消减。

14. 喝一杯(酒)
      To wet your whistle means to have a drink.

15. 徒然无功
      If you describe someone as whistling in the wind, you mean that they are trying unsuccessfully to change something which cannot be changed.

      e.g. The leader of the Liberal Democrats accused the Prime Minister of whistling in the wind to raise Conservative party morale.
             自由民主党领导人指责首相鼓舞保守党士气之举根本就是徒劳。