Illustration of merganser
merganser
noun
mer·gan·ser (ˌ)mər-ˈgan(t)-sər 
: any of various fish-eating diving ducks (especially genus Mergus) with a slender bill hooked at the end and serrated along the margins and usually a crested head see common merganser
Example Sentences
Recent Examples on the Web An odd thing is happening on a nearby pond: A hooded merganser seems to think a mallard hen is his mate and aggressively chases off any mallard males, even diving underwater like a submarine to come up under them to scare them away. 
Val Cunningham Special To The Star Tribune, Star Tribune, 15 June 2021 Sandra Critelli, a birder and photographer who saw the merganser, tells Gothamist that the duck was active, but unable to close its beak. Brigit Katz, Smithsonian Magazine, 25 Feb. 2020 The plan, NYC Parks press officer Megan Moriarty tells Gothamist, was to find the bird, remove the plastic and transport the merganser to the Wild Bird Fund, an animal rehabilitation center on New York’s Upper West Side. Brigit Katz, Smithsonian Magazine, 25 Feb. 2020 Many predators such as mountain lions, coyotes and bobcats are included in the proposals alongside game species such as mule deer, antelope and several bird species, including snipe, gallinule and merganser. Debra Utacia Krol, azcentral, 11 Apr. 2020 Along the Wachusett Reservoir there were two greater scaups at the Wachusett Dam, two red-breasted mergansers and three common loons at Rainbow Cove, and one common loon at North Dike. BostonGlobe.com, 9 Feb. 2020 Newly arrived wild ducks—buffleheads and hooded mergansers—circle in small groups near the shore. Sylvia Poggioli, The New York Review of Books, 29 Mar. 2020 Along the Wachusett Reservoir, there were 31 greater scaups at South Bay, three lesser scaups and four common loons at the Fletcher Street Bridge, three red-breasted mergansers at Rainbow Cove, and a Common Loon at the Clinton Dam. BostonGlobe.com, 11 Jan. 2020 And, in fact some swimmers do come in the winter: buffleheads, ring-necked ducks, mergansers and other waterfowl visiting from the north. New York Times, 18 Aug. 2019 See More
Val Cunningham Special To The Star Tribune, Star Tribune, 15 June 2021 Sandra Critelli, a birder and photographer who saw the merganser, tells Gothamist that the duck was active, but unable to close its beak. Brigit Katz, Smithsonian Magazine, 25 Feb. 2020 The plan, NYC Parks press officer Megan Moriarty tells Gothamist, was to find the bird, remove the plastic and transport the merganser to the Wild Bird Fund, an animal rehabilitation center on New York’s Upper West Side. Brigit Katz, Smithsonian Magazine, 25 Feb. 2020 Many predators such as mountain lions, coyotes and bobcats are included in the proposals alongside game species such as mule deer, antelope and several bird species, including snipe, gallinule and merganser. Debra Utacia Krol, azcentral, 11 Apr. 2020 Along the Wachusett Reservoir there were two greater scaups at the Wachusett Dam, two red-breasted mergansers and three common loons at Rainbow Cove, and one common loon at North Dike. BostonGlobe.com, 9 Feb. 2020 Newly arrived wild ducks—buffleheads and hooded mergansers—circle in small groups near the shore. Sylvia Poggioli, The New York Review of Books, 29 Mar. 2020 Along the Wachusett Reservoir, there were 31 greater scaups at South Bay, three lesser scaups and four common loons at the Fletcher Street Bridge, three red-breasted mergansers at Rainbow Cove, and a Common Loon at the Clinton Dam. BostonGlobe.com, 11 Jan. 2020 And, in fact some swimmers do come in the winter: buffleheads, ring-necked ducks, mergansers and other waterfowl visiting from the north. New York Times, 18 Aug. 2019 See More Word History
Etymology
New Latin, from Latin mergus, a waterfowl (from mergere) + anser goose — more at goose
First Known Use
1668, in the meaning defined above