lower vs come down

lower is a noun but come down is not a noun.

Word	Noun	Adjective	Verb	Adverb
lower	Yes	Yes	Yes	No
come down	No	No	Yes	No

lower (noun)	come down (noun)
the lower of two berths

lower (adjective)	come down (adjective)
the bottom one of two

lower (verb)	come down (verb)
make lower or quieter	get sick
set lower	be the essential element
cause to drop or sink	criticize or reprimand harshly
move something or somebody to a lower position	move downward and lower, but not necessarily all the way
look angry or sullen, wrinkle one's forehead, as if to signal disapproval	fall from clouds