1. 王国
    A kingdom is a country or region that is ruled by a king or queen.

    e.g. The kingdom's power declined.
           王国的势力衰弱了。
    e.g. ...the United Kingdom.
           联合王国

2. 管辖范围；领域
    A kingdom is a place or area that is thought to be under the control of a person or organization.

kingdom是什么意思

    e.g. It was infamous as a kingdom of brigands, scoundrels, and slave-traders.
           该地区因土匪、无赖和奴隶贩子猖獗而声名狼藉。

3. （动物或植物）界
    All the animals, birds, and insects in the world can be referred to together as the animal kingdom. All the plants can be referred to as the plant kingdom.