low relief vs high relief

low relief and high relief both are nouns.

Word	Noun	Adjective	Verb	Adverb
low relief	Yes	No	No	No
high relief	Yes	No	No	No

low relief (noun)	high relief (noun)
a sculptural relief in which forms extend only slightly from the background; no figures are undercut	a sculptural relief in which forms extend out from the background to at least half their depth