change posture vs stoop

change posture is not a noun while stoop is a noun.

Word	Noun	Adjective	Verb	Adverb
change posture	No	No	Yes	No
stoop	Yes	No	Yes	No

change posture (noun)	stoop (noun)
	an inclination of the top half of the body forward and downward
	small porch or set of steps at the front entrance of a house
	basin for holy water

change posture (verb)	stoop (verb)
undergo a change in bodily posture	carry oneself, often habitually, with head, shoulders, and upper back bent forward
	bend one's back forward from the waist on down
	descend swiftly, as if on prey
	sag, bend, bend over or down
	debase oneself morally, act in an undignified, unworthy, or dishonorable way