restlessness vs restless

restlessness is a noun but restless is not a noun.

Word	Noun	Adjective	Verb	Adverb
restlessness	Yes	No	No	No
restless	No	Yes	No	No

restlessness (noun)	restless (noun)
inability to rest or relax or be still
the quality of being ceaselessly moving or active
a feeling of agitation expressed in continual motion
a lack of patience; irritation with anything that causes delay

restlessness (adjective)	restless (adjective)
	lacking or not affording physical or mental rest
	worried and uneasy
	ceaselessly in motion
	nervous and unable to relax