fish duck

noun

, Informal.

1. merganser.

Word History and Origins

Origin of fish duck¹

An Americanism dating back to 1855–60

Example Sentences

The winter range of this "fish duck" is largely determined by the extent of open water on our lakes and streams.

From Project Gutenberg

Knowing a mallard from a merganser has another side: gourmets prefer a corn-fed mallard to the fish duck.

From Project Gutenberg

The name fish-duck, which one hears occasionally, is much more appropriate.

From Project Gutenberg

Not a living creature but a fish duck peacefully riding the water was to be seen.

From Project Gutenberg