sorry vs drab

sorry is not a noun while drab is a noun.

Word	Noun	Adjective	Verb	Adverb
sorry	No	Yes	No	No
drab	Yes	Yes	No	No

As adjectives, sorry and drab are synonyms defined as:

Other synonyms of sorry include blue, dark, dingy, disconsolate, dismal, drear, dreary, gloomy, grim.

sorry (noun)	drab (noun)
	a dull greyish to yellowish or light olive brown

sorry (adjective)	drab (adjective)
feeling or expressing regret or sorrow or a sense of loss over something done or undone	of a light brownish green color
bad; unfortunate	lacking brightness or color; dull
causing dejection	causing dejection
without merit; of little or no value or use	lacking in liveliness or charm or surprise