The Collaborative International Dictionary
Unnecessariness
Unnecessary \Un*nec"es*sa*ry\, a. Not necessary; not required under the circumstances; unless; needless; as, unnecessary labor, care, or rigor. -- Un*nec"es*sa*ri*ly, adv. -- Un*nec"es*sa*ri*ness, n.
Wiktionary
unnecessariness
n. The state or characteristic of being unnecessary.