What does "iron" mean?

Tiezi refers to a close and unintentional friend.

Usage: Iron seeds are often used in the northern region, between brothers in the northern region. There are also between the opposite sex, but they are rarely used. Generally speaking, it is the relationship between bosom friend and bosom friend. This word can be used between men and women as well as between men and women. It has also become a network term.

Brief introduction of network terms:

Internet slang refers to a language that is produced on the Internet or used in online communication, including Chinese and English letters, punctuation marks, symbols, pinyin, icons (pictures) and characters. This combination often shows special significance in specific network media communication. In the early 1990s, the ways used by netizens to improve the efficiency of online chatting or humor have gradually formed a specific language.

With the innovation of internet technology, this language form has developed rapidly in the spread of internet media in the past ten years since it entered the 2/kloc-0 century. Network language is becoming an indispensable part of people's network life. However, it should be noted that some online languages do not conform to the grammatical provisions of modern Chinese, so they have no teaching significance and cannot be introduced into the teaching field.