A river flowing from lake Esgaroth into the river Carnen, translated “River Running” (LotR/1046). It is most likely a combination of some form of the root √KEL “flow” and S. duin “duin”.
noun. running river
place name. River Running
Word Gloss KEL “flow (down or away), run (of water or rivers), go away, flow (down or away), run (of water or rivers), go away, [ᴹ√] run away especially downwards or at end; [ᴱ√] ooze, trickle” duin “(large) river, (large) river; [N.] water”
cell (adj. “running, flowing”) + duin (“big and large river”)