ant bird vs ant shrike

ant bird and ant shrike both are nouns.

Word	Noun	Adjective	Verb	Adverb
ant bird	Yes	No	No	No
ant shrike	Yes	No	No	No

As nouns, ant shrike is a hyponym of ant bird; that is, ant shrike is a word with a more specific, narrower meaning than ant bird:

ant bird: any of various dull-colored South American birds that feeding on ants some following army ant swarms
ant shrike: antbirds superficially resembling shrikes

Other hyponyms of ant bird include ant thrush, Hylophylax naevioides, spotted antbird.

ant bird (noun)	ant shrike (noun)
any of various dull-colored South American birds that feeding on ants some following army ant swarms	antbirds superficially resembling shrikes