1. (粉刷用的)石灰水，白涂料
    Whitewash is a mixture of lime or chalk and water that is used for painting walls white.

2. 用石灰水粉刷
    If a wall or building has been whitewashed, it has been painted white with whitewash.

    e.g. The walls had been whitewashed.
           墙已经用石灰水刷过了。
    e.g. ...a town of picturesque whitewashed cottages.
           一座座小屋粉刷得洁白而漂亮的城镇

3. 粉饰;掩饰
    If you say that people whitewash something, you are accusing them of hiding the unpleasant facts or truth about it in order to make it acceptable.

    e.g. The administration is whitewashing the regime's actions...
           政府在粉饰该政权的行为。
    e.g. 'The whole incident was whitewashed,' he claimed yesterday.
           “整个事件都已经被粉饰过了，”他昨日声称。

4. 粉饰;掩饰
    Whitewash is an attempt to hide the unpleasant facts or truth about someone or something.

    e.g. He pledged that there would be no whitewash and that the police would carry out a full investigation...
           他保证将不会有任何掩饰，并且警方将进行全面调查。
    e.g. The report's findings were condemned as total whitewash.
           这份报告最后的结论被谴责为彻头彻尾的粉饰。

5. 轻易战胜；使（对手）得零分
    In sports, if a player or team whitewashes an opponent, they win very easily, and their opponent does not get any points at all.

whitewash

    e.g. Not since 1988 had she whitewashed an opponent in her opening match...
           自1988年以来她还从未在开场赛中让对手吃过鸭蛋。
    e.g. Their leading players were being whitewashed 4-0.
           他们的主力阵容以0比4惨败。