greenish blue vs peacock blue

greenish blue and peacock blue both are nouns.

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

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

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

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