grey-green vs grayish-green

grey-green and grayish-green both are adjectives.

Word	Noun	Adjective	Verb	Adverb
grey-green	No	Yes	No	No
grayish-green	No	Yes	No	No

As adjectives, grey-green and grayish-green are synonyms defined as:

Other synonyms of grey-green include gray-green, greyish-green.

grey-green (adjective)	grayish-green (adjective)
of green tinged with grey	of green tinged with grey