wood widgeon vs summer duck

wood widgeon and summer duck both are nouns.

Word	Noun	Adjective	Verb	Adverb
wood widgeon	Yes	No	No	No
summer duck	Yes	No	No	No

As nouns, wood widgeon and summer duck are synonyms defined as:

wood widgeon and summer duck: showy North American duck that nests in hollow trees

Other synonyms of wood widgeon include Aix sponsa, wood duck.

wood widgeon (noun)	summer duck (noun)
showy North American duck that nests in hollow trees	showy North American duck that nests in hollow trees