[1] : The Collaborative International Dictionary of English v.0.48

goosander \goos"an`der\, n. oe. gossander, a tautological word
   formed fr. goose + gander. cf. merganser. zool.
   a species of merganser m. merganser of northern europe
   and america; -- called also merganser, dundiver,
   sawbill, sawneb, shelduck, and sheldrake. see
   merganser.
   1913 webster
see also:
merganser m. merganser merganser dundiver sawbill sawneb 
shelduck sheldrake 

[2] : The Collaborative International Dictionary of English v.0.48

merganser \mergan"ser\, n. sp. merg'ansar, fr. mergo a diver
   l. mergus, fr. mergere to dip, dive + 'ansar goose, l.
   anser. zool.
   any bird of the genus mergus merganser, and allied
   genera of the subfamily merginae. they are allied to the
   ducks, but have a sharply serrated bill, eat fish, and dive
   for food. also called fish duck.
   1913 webster +pjc

   note: the red-breasted merganser merganser serrator
         inhabits both hemispheres. it is called also sawbill,
         harle, and sheldrake. the american merganser
         merganser americanus. and the hooded merganser
         lophodytes cucullatus are well-known species.

   white merganser, the smew or white nun.
      1913 webster
see also:
mergus merganser fish duck merganser serrator sawbill harle 
sheldrake merganser americanus lophodytes cucullatus white merganser 

[3] : WordNet (r) 2.0

merganser
     n : large crested fish-eating diving duck having a slender
         hooked bill with serrated edges syn: fish duck, sawbill,
          sheldrake
see also:
fish duck sawbill sheldrake 

Merganser >> M Words
Merganser, definition of term: Merganser
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