re-entrant vs salient

re-entrant is not a noun while salient is a noun.

Word	Noun	Adjective	Verb	Adverb
re-entrant	No	Yes	No	No
salient	Yes	Yes	No	No

re-entrant (noun)	salient (noun)
	(military) the part of the line of battle that projects closest to the enemy

re-entrant (adjective)	salient (adjective)
(of angles) pointing inward	(of angles) pointing outward at an angle of less than 180 degrees
	having a quality that thrusts itself into attention
	represented as leaping (rampant but leaning forward)