sitting vs nonmoving

sitting is a noun but nonmoving is not a noun.

Word	Noun	Adjective	Verb	Adverb
sitting	Yes	Yes	No	No
nonmoving	No	Yes	No	No

sitting (noun)	nonmoving (noun)
the act of assuming or maintaining a seated position
(photography) the act of assuming a certain position (as for a photograph or portrait)
a session as of a legislature or court
a meeting of spiritualists

sitting (adjective)	nonmoving (adjective)
(of persons) having the torso erect and legs bent with the body supported on the buttocks	not in motion
not moving and therefore easy to attack