Source : Webster's Revised Unabridged Dictionary (1913)

Unnesessary \Un*nes"es*sa*ry\, a.
   Not necessary; not required under the circumstances; unless;
   needless; as, unnecessary labor, care, or rigor. --
   {Un*nes"es*sa*ri*ly}, adv. -- {Un*nes"es*sa*ri*ness}, n.