Tolkien never directly translates the name Ringló himself, but the elements ring 'cold' and ló 'flood, fen' are well established. The ló element is commonly seen in the names of rivers that flooded the lands around them, or flowed through fenlands: compare, for example, Gwathló ('Greyflood') or Onodló ('Entwash'). In fact, it seems that in this case the flooding was of a mountain tarn that formed the river's source, which swelled to a lake at times of snowmelt.