solace vs calm down

solace is a noun but calm down is not a noun.

Word	Noun	Adjective	Verb	Adverb
solace	Yes	No	Yes	No
calm down	No	No	Yes	No

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

Other hyponyms of solace include calm, lull, quiet, quieten, still, tranquilize, tranquillise, tranquillize, allay, ease, relieve, still.

solace (noun)	calm down (noun)
the act of consoling; giving relief in affliction
the comfort you feel when consoled in times of disappointment
comfort in disappointment or misery

solace (verb)	calm down (verb)
give moral or emotional strength to	become quiet or less intensive
	make calm or still
	become quiet or calm, especially after a state of agitation