不断
búduàn · HSK 3
continuously
♾️ 不 = not + 断 = break/sever → 'not breaking' = unceasing
断 means to cut, break, or sever (think 断开 = disconnect). Negating it with 不 gives 'not severed', i.e. continuous flow. Common in 不断进步 (constant progress) and 源源不断 (an unending stream).
不 — single pictograph; bird flying upward
Originally a pictograph in oracle bone script, traditionally interpreted as a bird flying up toward the sky and unable to come down, suggesting negation or refusal. Over time it became the standard negation word in Chinese, used before verbs and adjectives to mean 'not'.
断 — thread 㡭 (silk bundle) + axe 斤
Originally written with 㡭 (entangled silk threads) on the left and 斤 (axe) on the right, depicting an axe cutting through bundled threads. From this concrete image of severing came the meanings 'to cut off,' 'to break,' and by extension 'to decide' or 'judge'—as in resolving a matter decisively.