Lac Léman, is the french word for what english people call lake geneva (all the region around lac léman is french speaking).

Léman comes from celtic “lemann” which means lake.

So lac léman is the lake lake. Given it is the biggest lake in western europe, not a bad name.

Lake Tahoe is a mispronunciation of a native word that kinda means lake. Lake Michigan is literally lake large lake. There’s a lake in the UK called lake semerwater which literally means lake lake lake.

The list is quite extensive.