knight vs knightly

knight is a noun but knightly is not a noun.

Word	Noun	Adjective	Verb	Adverb
knight	Yes	No	Yes	No
knightly	No	Yes	No	No

knight (noun)	knightly (noun)
a chessman shaped to resemble the head of a horse; can move two squares horizontally and one vertically (or vice versa)
originally a person of noble birth trained to arms and chivalry; today in Great Britain a person honored by the sovereign for personal merit

knight (adjective)	knightly (adjective)
	being attentive to women like an ideal knight
	characteristic of the time of chivalry and knighthood in the Middle Ages

knight (verb)	knightly (verb)
raise (someone) to knighthood