ibis vs sacred ibis

ibis and sacred ibis both are nouns.

Word	Noun	Adjective	Verb	Adverb
ibis	Yes	No	No	No
sacred ibis	Yes	No	No	No

As nouns, sacred ibis is a hyponym of ibis; that is, sacred ibis is a word with a more specific, narrower meaning than ibis:

Other hyponyms of ibis include Ibis ibis, wood ibis, wood stork, Threskiornis aethiopica.

ibis (noun)	sacred ibis (noun)
wading birds of warm regions having long slender down-curved bills	African ibis venerated by ancient Egyptians