anxiousness vs anxious

anxiousness is a noun but anxious is not a noun.

Word	Noun	Adjective	Verb	Adverb
anxiousness	Yes	No	No	No
anxious	No	Yes	No	No

anxiousness (noun)	anxious (noun)
a feeling of mild anxiety about possible developments
(psychiatry) a relatively permanent state of worry and nervousness occurring in a variety of mental disorders, usually accompanied by compulsive behavior or attacks of panic

anxiousness (adjective)	anxious (adjective)
	eagerly desirous
	causing or fraught with or showing anxiety