As a noun songbird
is a bird having a melodious song or call.
As an adjective nonpasserine is
As adjectives the difference between passerine and nonpasserine
is that passerine
is of, or relating to a passerine or perching bird while nonpasserine
is not passerine.
As a noun passerine
is any bird of the order passeriformes, which comprises more than half of all bird species.