Etymology

Old Chinese *guːnʔ duːnʔ. The variant 渾淪／浑沦 (húnlún) suggests that this perhaps came from *guːnʔ l̥uːnʔ ~ guːnʔ ruːnʔ, from **gruːnʔ, from the root *k(V)r- ("to flow > to mix > to be turbid, chaotic").

Related to 餛飩／馄饨 (húntún, “wonton”) and 雲吞／云吞 (yúntūn, “wonton”).

Compare 渾 (OC *ɡuːn, *ɡuːnʔ), 混 (OC *ɡuːnʔ, “rapidly flowing water; turbidity; confusedness; unclearness; big; whole”), Korean 흐르다 (heureuda, “to flow; to float; to fill”), 흐리다 (heurida, “to be turbid, unclear, indistinct”), 흐릿하다 (heurithada, “to be vague, indistinct”).

Pronunciation