ibis vs Ibis ibis

ibis and Ibis ibis both are nouns.

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

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

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

ibis (noun)	Ibis ibis (noun)
wading birds of warm regions having long slender down-curved bills	any of several Old World birds of the genus Ibis