What does the word ‘best friend’ in ‘my best friend’ mean?

"Best friend" actually means "good friend", and it goes one step further. It is a friend who is easy to talk to and very trustworthy.

The biggest difference between "best friends" and "friends" is that friends value friendship, while best friends value loyalty.

The Chinese dictionary’s explanation of best friends

1. Do your best to serve your friends.

"The Biography of Zhai Fangjin in the Book of Han Dynasty": "After the case, General Zhu Bo, Julu Prefect Sun Hong, and Guanglu doctor Chen Xian had a good relationship with Li, and they were close friends. "Believe, if you want to support each other, you will die." Yan Shigu notes: "A best friend is a friend who works hard for a friend."

2. A party member who works hard for someone or a group. Contains derogatory meaning.

Song Lu You's "Book of the Southern Tang·Chen Jue Biography": "After a year, [Chen Jue] resumed his duties, and he and Zheng Gu became buddies, advocating peace and harmony with each other."

"History of the Song Dynasty·Biography of Traitors III·Qin Hui": "Jun (Zhang Jun) was in Yongzhou, and Hui (Qin Hui) made his best friend Zhang Bing know about Tanzhou."

Hu Shi's "Study Methods of Scholars in the Qing Dynasty" ": "This shows that the methods of sinologists are so sophisticated that even the best friends of Song Dynasty can't help but be convinced."