He was fairly beside himself with joy. 翻译

1.beside himself 是一个词组。

英[bi?said him?self] 美[bsa?d h?m?s?lf]

[词典] 发狂，疯癫;

[例句]He had shouted down the phone at her, beside himself with anxiety

他焦急万分地对着电话那头的她大喊大叫。

2.He was fairly beside himself with joy.全句意思是他欢喜欲狂。