We dubbed him Fatty.是什么意思？

We dubbed him Fatty.

我们给他起了个绰号叫“胖子”.

we

pron. 我们，咱们，笔者，本人，朕，人们；

例句
...expensive make-up that we saw being advertised by a beautiful model...
我们所见的由一位漂亮模特代言的昂贵化妆品

Dubbed

v. 给…起绰号( dub的过去式和过去分词 )，把…称为，配音，复制；

例句
...the man whom the Labour opposition dubbed as the 'no change Prime Minister'...
被工党反对派戏称为“不变首相”的男人

him

pron. (he的宾格)他；

例句
They said goodbye to him as he got aboard the train at Union Station.
当他在联合火车站登上火车之际，他们向他道别。

fatty

adj. 油腻的，肥胖的，多脂肪的；n. 胖子；

例句
There's a lot of evidence that oily fish, as distinct from fatty meat, has a beneficial effect.
有许多证据表明油性鱼，与高脂肪肉不同，对人体有益。