drear vs drab

drear is not a noun while drab is a noun.

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

As adjectives, drear and drab are synonyms defined as:

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

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

drear (adjective)	drab (adjective)
causing dejection	of a light brownish green color
	lacking brightness or color; dull
	causing dejection
	lacking in liveliness or charm or surprise