His eyes were green.
You didn't want to say, like emeralds, or grass, or trees, or the deep of the sea. You didn't want to compare his eyes to a slowly growing houseplant on your kitchen counter. You weren't going to pour yourself a glass of Chartreuse whilst musing on how the colour so matches his eyes. When you took a bite out of an apple you wouldn't sit back and try and pick out the shades on the skin that you could find in his eyes.
They were just really, freaking green.
And perfectly incomparable.