酸溜溜 is a reduplicated adjective that literally evokes the sharp, tangy taste of sour food—like unripe plums or vinegar—but is used far more often in a figurative sense to describe the uncomfortable, prickly feeling of jealousy or envy. The first character 酸 (suān) means 'sour', while the repeated 溜溜 (liū liū) adds an expressive, colloquial tone, intensifying the sensation and lending it a slightly exaggerated, almost playful or self-aware quality.

This word appears frequently in informal speech and writing when someone feels envious—not in a hostile way, but with a twinge of self-consciousness or wry amusement. It often carries a light, humorous, or mildly self-deprecating nuance, especially when describing reactions to others’ success, attention, or good fortune. Unlike stronger terms like 嫉妒 (jí dù), 酸溜溜 softens the edge of envy, making it socially acceptable to admit—even laugh at—one’s own pangs of comparison.