"Lèi mù" literally means "tear-filled eyes"—combining 泪 (lèi, "tear") and 目 (mù, "eye" or "eyes"). Though composed of two concrete nouns, it functions idiomatically as a noun describing an emotional state: the visible physical sign of being deeply moved, touched, or overwhelmed—often by something heartwarming, sad, nostalgic, or inspiring. It’s not about crying uncontrollably, but rather the tender, tear-glistening moment just before or during quiet emotion.

This term is widely used in informal digital communication—especially on social media, forums, and comment sections—to express empathetic resonance. It carries warmth and sincerity, rarely irony or sarcasm. Unlike formal literary terms for weeping, 泪目 is colloquial, concise, and emotionally immediate, often appearing after descriptions of moving events, reunions, acts of kindness, or personal triumphs.