wagtail vs oscine bird

wagtail and oscine bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
wagtail	Yes	No	No	No
oscine bird	Yes	No	No	No

As nouns, oscine bird is a hypernym of wagtail; that is, oscine bird is a word with a broader meaning than wagtail:

wagtail: Old World bird having a very long tail that jerks up and down as it walks
oscine bird: passerine bird having specialized vocal apparatus

Other hypernyms of wagtail include oscine.

wagtail (noun)	oscine bird (noun)
Old World bird having a very long tail that jerks up and down as it walks	passerine bird having specialized vocal apparatus