Where does “merganser” come from?

merganser (English) comes from Late Latin merganser, from Latin mergus, from Latin mergō, from Proto-Indo-European *mésgeti, from Proto-Indo-European mesg- — to dip, sink.

merganser (English): Any of various diving ducks of the genera...

Definitions

Any of various diving ducks of the genera...

Ancestry of “merganser”, step by step

Step	Language	Word	Meaning
1	Late Latin	merganser	—
2	Latin	mergus	diver (loon), a kind of waterfowl
3	Latin	mergō	to dip (in), immerse; plunge into water; drown
4	Proto-Indo-European	*mésgeti	to sink
5	Proto-Indo-European	mesg-	to dip, sink

Every word from Proto-Indo-European mesg- →Every word from Proto-Indo-European *mésgeti →Every word from Latin mergō →