面 miàn is a pictograph of a face drawn inside its own outline. The oracle-bone form encloses an eye within a boundary that traces the edge of the head, so the whole character means "the bounded front of the head," the face as the surface you turn toward the world. The single eye in the early form stands for the whole countenance. The modern shape keeps the outer frame and the features packed inside it.

From "the face you present" the meaning opened outward in a straight line. A face is a surface, so 面 came to mean any surface or side; a surface seen one way among many became an aspect or facet; a flat thing measured by its faces gave 面 its life as a measure word. Three senses fall out:

1. Face, facing. The literal countenance and the act of turning toward: 脸面 liǎnmiàn (face), 面对 miànduì (to face), 面前 miànqián (in front of), 面子 miànzi (face in the social sense, prestige).
2. Surface, side, aspect. 表面 biǎomiàn (surface), 方面 fāngmiàn (aspect), and the locational set 上面 shàngmiàn (above), 下面 xiàmiàn (below), 外面 wàimiàn (outside), 里面 lǐmiàn (inside).
3. Measure word for flat objects. 一面镜子 yī miàn jìngzi (a mirror), 一面墙 yī miàn qiáng (a wall), 一面旗 yī miàn qí (a flag).

There is one more sense that is purely a matter of script. In traditional writing, "flour" and "noodles" were a separate character, 麵 (also written 麪), built on the 麦 mài wheat radical. The simplified reform folded 麵 into 面, so today a single 面 carries both the ancient "face" and the unrelated "flour, noodles." Context, never the glyph, tells them apart: 洗面 means wash the face, 吃面 means eat noodles.

Once a face is also a surface, 面 becomes the language's standard way of naming sides and aspects. A thing seen from the front shows one 面; turn it and another 面 appears. From this come 方面 fāngmiàn (an aspect of a matter, literally a "direction-face"), 表面 biǎomiàn (the outer surface, often with the sense of mere appearance), 全面 quánmiàn (all-sided, comprehensive), and 片面 piànmiàn (one-sided, partial).

The same logic powers the everyday locational words. 面 attaches to a direction to name the region on that side: 上面 shàngmiàn (the side above), 下面 xiàmiàn (below), 外面 wàimiàn (outside), 里面 lǐmiàn (inside), 后面 hòumiàn (behind), 前面 qiánmiàn (in front). Each is literally a "face" of the space around you.

This whole family has nothing to do with faces. In traditional script it belonged to a different character, 麵 miàn (also written 麪), built on the 麦 mài wheat radical, meaning ground wheat: flour and the noodles made from it. When characters were simplified, 麵 was merged into the much simpler 面, and the two senses have shared one glyph ever since. On a menu, every 面 is wheat: 面条 miàntiáo (noodles), 面包 miànbāo (bread), 方便面 fāngbiànmiàn (instant noodles).

Start with the face drawn inside its outline. That face is the surface you turn toward the world, so 面 is the front you present (面对, 见面) and the standing you hold in others' eyes (面子). Tilt the face flat and it becomes a plain surface (表面), then any side or aspect of a thing (方面), then the region on each side of you (上面, 里面, 外面). Lay it down completely and it counts flat objects: 一面镜子, a mirror.

The noodles are the trick. They were never a face at all, just the old wheat character 麵 that simplified writing dropped onto the same glyph. So when 面 appears at the dinner table, forget the face entirely and think only of flour: 面条, 面包, a bowl of wheat.