Source : Webster's Revised Unabridged Dictionary (1913)

Unconstant \Un*con"stant\, a.
   Not constant; inconstant; fickle; changeable. [Obs.] --Shak.
   -- {Un*con"stant*ly}, adv. [Obs.] -- {Un*con"stant*ness}, n.
   [Obs.]