levelness vs straightness

levelness and straightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
levelness	Yes	No	No	No
straightness	Yes	No	No	No

As nouns, straightness is a hypernym of levelness; that is, straightness is a word with a broader meaning than levelness:

levelness: The property of being the same height at all places; parallel to a flat ground.
straightness: freedom from crooks or curves or bends or angles

levelness (noun)	straightness (noun)
The property of being the same height at all places; parallel to a flat ground.	a sexual attraction to (or sexual relations with) persons of the opposite sex
	freedom from crooks or curves or bends or angles
	(of hair) lack of a tendency to curl
	having honest intentions
	trueness of course toward a goal