spectacled caiman vs cayman

spectacled caiman and cayman both are nouns.

Word	Noun	Adjective	Verb	Adverb
spectacled caiman	Yes	No	No	No
cayman	Yes	No	No	No

As nouns, cayman is a hypernym of spectacled caiman; that is, cayman is a word with a broader meaning than spectacled caiman:

spectacled caiman: caiman with bony ridges about the eyes; found from southern Mexico to Argentina
cayman: a semiaquatic reptile of Central and South America that resembles an alligator but has a more heavily armored belly

Other hypernyms of spectacled caiman include caiman.

spectacled caiman (noun)	cayman (noun)
caiman with bony ridges about the eyes; found from southern Mexico to Argentina	a semiaquatic reptile of Central and South America that resembles an alligator but has a more heavily armored belly