cast down vs chill

cast down is not a noun while chill is a noun.

Word	Noun	Adjective	Verb	Adverb
cast down	No	No	Yes	No
chill	Yes	No	Yes	No

As verbs, chill is a hyponym of cast down; that is, chill is a word with a more specific, narrower meaning than cast down:

cast down (noun)	chill (noun)
	coldness due to a cold environment
	a sudden numbing dread
	an almost pleasurable sensation of fright
	a sensation of cold that often marks the start of an infection and the development of a fever

cast down (verb)	chill (verb)
lower someone's spirits; make downhearted	loose heat
	make cool or cooler
	depress or discourage