The Vietnamese word "ai oán" is an adjective that describes a feeling or sound that is mournful, sad, or plaintive. It is often used to express sorrow, lamentation, or a deep sense of loss.
Giọng ai oán - "a plaintive voice"
Tiếng khóc than ai oán - "plaintive cries"
Những bài hát ai oán - "plaintive songs"
In summary, "ai oán" is a descriptive term used to express deep sadness or mourning in various contexts, especially relating to voices, songs, or emotional expressions.