dullness vs contour

dullness and contour both are nouns.

Word	Noun	Adjective	Verb	Adverb
dullness	Yes	No	No	No
contour	Yes	No	Yes	No

As nouns, contour is a hypernym of dullness; that is, contour is a word with a broader meaning than dullness:

Other hypernyms of dullness include configuration, conformation, form, shape.

dullness (noun)	contour (noun)
lack of sensibility	any spatial attributes (especially as defined by outline)
without sharpness or clearness of edge or point	a feature (or the order or arrangement of features) of anything having a complex structure
the quality of lacking interestingness	a line drawn on a map connecting points of equal height
a lack of visual brightness
the quality of being slow to understand

dullness (verb)	contour (verb)
	form the contours of