downgrade vs rate

downgrade and rate both are nouns.

Word	Noun	Adjective	Verb	Adverb
downgrade	Yes	No	Yes	No
rate	Yes	No	Yes	No

As verbs, rate is a hypernym of downgrade; that is, rate is a word with a broader meaning than downgrade:

Other hypernyms of downgrade include grade, order, place, range, rank.

downgrade (noun)	rate (noun)
the property possessed by a slope or surface that descends	the relative speed of progress or change
	amount of a charge or payment relative to some basis
	a quantity or amount or measure considered as a proportion of another quantity or amount or measure
	a magnitude or frequency relative to a time unit

downgrade (verb)	rate (verb)
rate lower; lower in value or esteem	assign a rank or rating to
	estimate the value of
	be worthy of or have a certain rating