Men (pinyin: mén) is a first-class Chinese character (commonly used word) in the General Standard of Chinese. This word first appeared in Shang Dynasty Oracle Bone Inscriptions and Shang Dynasty inscriptions, and its ancient glyph looks like two gates. The original meaning of the door refers to the two outer doors of the house, which are opposite to the residents as inner doors. The door is the only place for people to enter and leave the house, and it is also extended as a way. Doors are generally built in the house at home, extending from the house to families, clans, and different factions and categories, especially religious and academic groups and factions. Doors can also be used as quantifiers.

The ideographic character "door" in Oracle Bone Inscriptions is as shown in Figure 1 or Figure 2, which consists of two doors, or there are bars on the two doors. The "gate" in Oracle Bone Inscriptions reflects the structure of the gate in the late Shang Dynasty. From Wen Jia style to regular script, the shapes are the same, that is, the left and right sides are vertical like the door axis, and the opposite side is like the facade, just like the door, which seems to be a single pictograph. However, Shuo Wen Jie Zi is interpreted as consisting of two households, each of which is originally a single household, and can be written in positive and negative directions without affecting its sound and meaning, and belongs to a unique hieroglyph. Then the door is not only composed of two unique hieroglyphs, but also has no sound relationship with the residents. Therefore, "door" is a cognitive word.

As the name implies, "door" is the shelter of the entrance and exit of the house. A family usually lives in a door, and the door is also the entrance to a family. The word "door" is extended to mean "home", "home" and "family status". Everything similar to "door" in daily life is often called "door", which is an entrance and exit. Words such as "valve", "valve" and "throttle" are derived from this feature. The door is characterized by a single family, from which there is a faction, so it can be said that "sects" and "classes" and so on.