inkiness vs achromatic color

inkiness and achromatic color both are nouns.

Word	Noun	Adjective	Verb	Adverb
inkiness	Yes	No	No	No
achromatic color	Yes	No	No	No

As nouns, achromatic color is a hypernym of inkiness; that is, achromatic color is a word with a broader meaning than inkiness:

inkiness: the quality or state of the achromatic color of least lightness (bearing the least resemblance to white)
achromatic color: a color lacking hue; white or grey or black

Other hypernyms of inkiness include achromatic colour.

inkiness (noun)	achromatic color (noun)
the quality or state of the achromatic color of least lightness (bearing the least resemblance to white)	a color lacking hue; white or grey or black