自主
zìzhǔ · HSK 3
be one's own master
自 (self) + 主 (master) = self-master, acting on one's own initiative
自 means self; 主 means master or host. Together: being one's own master. Contrast with 自动 (self + move = automatic) — 自主 is about agency and autonomy, not mechanism.
自 — pictograph of a nose
自 originally depicted a human nose, shown frontally with the bridge and nostrils. Ancient Chinese pointed to their own nose to mean 'me,' so 自 shifted to mean 'self' or 'oneself.' A new character 鼻 was later created to carry the original 'nose' meaning.
主 — flame/lamp on top of a stand 王
Originally a pictograph of a lamp with a flame on top of its stand, representing the lord or master of the household who tended the fire. The meaning extended from 'lamp/host' to 'master, owner, main, principal'. The character 炷 (wick) preserves the original 'lamp' sense.