'Tāng hún shuǐ' literally means 'to wade into muddy water' — a vivid metaphor where 'tāng' (to wade) evokes physical effort and risk, 'hún' (murky/turbid) suggests confusion or moral ambiguity, and 'shuǐ' (water) represents the situation itself. Together, the phrase conveys deliberately entering a complicated, potentially dangerous, or ethically questionable affair — often one involving conflict, corruption, or hidden agendas.

The expression carries a strong negative connotation: it implies recklessness, poor judgment, or unnecessary entanglement. It's commonly used in warnings ('Don’t go tāng hún shuǐ!') or retrospective criticism ('He shouldn’t have tāng hún shuǐ in that business dispute'). Unlike neutral terms for involvement (e.g., cānyù), this phrase always implies undesirable consequences or compromised integrity — much like 'stirring up trouble' or 'muddying the waters' in English, but with stronger emphasis on personal risk and moral compromise.