àohuǐ is a compound word expressing deep, painful regret—often for a serious mistake or moral failure. The first character 懊 (ào) conveys inner distress or anguish, while the second character 悔 (huǐ) means 'to regret' or 'to repent.' Together, they intensify the emotional weight beyond ordinary regret: àohuǐ suggests self-reproach, sorrow, and sometimes a desire to undo the past. It is commonly used in formal writing, literature, and reflective speech—not in casual conversation.

This word often appears after verbs like 'feel,' 'experience,' or 'be filled with,' and frequently co-occurs with phrases indicating cause (e.g., 因为...而懊悔 — 'regret ... because of ...') or duration (e.g., 长久懊悔 — 'long-lasting remorse'). It carries a solemn, introspective tone and implies the person recognizes their responsibility for the wrongdoing or misjudgment.