aqua vs peacock blue

aqua and peacock blue both are nouns.

Word	Noun	Adjective	Verb	Adverb
aqua	Yes	No	No	No
peacock blue	Yes	No	No	No

As nouns, aqua and peacock blue are synonyms defined as:

Other synonyms of aqua include aquamarine, cobalt blue, greenish blue, turquoise.

aqua (noun)	peacock blue (noun)
a shade of blue tinged with green	a shade of blue tinged with green