wood duck vs summer duck

wood duck and summer duck both are nouns.

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

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

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

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

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