whistler vs goldeneye

whistler and goldeneye both are nouns.

Word	Noun	Adjective	Verb	Adverb
whistler	Yes	No	No	No
goldeneye	Yes	No	No	No

As nouns, whistler and goldeneye are synonyms defined as:

whistler and goldeneye: large-headed swift-flying diving duck of Arctic regions

Other synonyms of whistler include Bucephela clangula.

whistler (noun)	goldeneye (noun)
Australian and southeastern Asian birds with a melodious whistling call	large-headed swift-flying diving duck of Arctic regions
large-headed swift-flying diving duck of Arctic regions	a variety of green lacewing
large North American mountain marmot
someone who makes a loud high sound