water ice vs black ice

water ice and black ice both are nouns.

Word	Noun	Adjective	Verb	Adverb
water ice	Yes	No	No	No
black ice	Yes	No	No	No

As nouns, black ice is a hyponym of water ice; that is, black ice is a word with a more specific, narrower meaning than water ice:

water ice: water frozen in the solid state
black ice: a thin coating of ice (as from freezing mist) on a road or sidewalk; nearly invisible but very hazardous

Other hyponyms of water ice include frost, hoar, hoarfrost, rime, hailstone, icicle, ground ice, segregated ice, Taber ice.

water ice (noun)	black ice (noun)
an ice containing no milk but having a mushy consistency; usually made from fruit juice	a thin coating of ice (as from freezing mist) on a road or sidewalk; nearly invisible but very hazardous
water frozen in the solid state