tailorbird vs Old World warbler

tailorbird and Old World warbler both are nouns.

Word	Noun	Adjective	Verb	Adverb
tailorbird	Yes	No	No	No
Old World warbler	Yes	No	No	No

As nouns, Old World warbler is a hypernym of tailorbird; that is, Old World warbler is a word with a broader meaning than tailorbird:

tailorbird: tropical Asian warbler that stitches leaves together to form and conceal its nest
Old World warbler: small active brownish or greyish Old World birds

Other hypernyms of tailorbird include true warbler.

tailorbird (noun)	Old World warbler (noun)
tropical Asian warbler that stitches leaves together to form and conceal its nest	small active brownish or greyish Old World birds