lour vs scowl

lour is not a noun while scowl is a noun.

Word	Noun	Adjective	Verb	Adverb
lour	No	No	Yes	No
scowl	Yes	No	Yes	No

As verbs, scowl is a hyponym of lour; that is, scowl is a word with a more specific, narrower meaning than lour:

lour: look angry or sullen, wrinkle one's forehead, as if to signal disapproval
scowl: frown with displeasure

lour (noun)	scowl (noun)
	a facial expression of dislike or displeasure

lour (verb)	scowl (verb)
look angry or sullen, wrinkle one's forehead, as if to signal disapproval	frown with displeasure
make lower or quieter
set lower