Lethe \l(e)-the\ as a girl's name is a variant of Leith (Scottish, Gaelic) and Letha (Greek), and the meaning of Lethe is "broad river; forgetfulness".

The baby name Lethe sounds like Leithe, Letty, Lettie, Lettee, Lotte, Leta, Lethia, Leitha, Letta and Lotie. Other similar baby names are Leese, Leece, Lesha, Retha, Lene, Lee, Beth, Betha, Bethea, Cathe, Bethie, Jeth, Kathe, Kaethe, Leah, Leone, Lenae and Ruthe.