grade vs downgrade

grade and downgrade both are nouns.

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

As nouns, downgrade is a hyponym of grade; that is, downgrade is a word with a more specific, narrower meaning than grade:

Other hyponyms of grade include rise, rising slope, upgrade.

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

grade (noun)	downgrade (noun)
a variety of cattle produced by crossbreeding with a superior breed	the property possessed by a slope or surface that descends
a position on a scale of intensity or amount or quality
the gradient of a slope or road or other surface
the height of the ground on which something stands
a number or letter indicating quality (especially of a student's performance)
a degree of ablaut
a body of students who are taught together
one-hundredth of a right angle
a relative position or degree of value in a graded group

grade (verb)	downgrade (verb)
determine the grade of or assign a grade to	rate lower; lower in value or esteem
assign a rank or rating to
assign a grade or rank to, according to one's evaluation
level to the right gradient