The Collaborative International Dictionary of English v.0.48:

Nitency \Ni"ten*cy\, n. [L. nitens, p. pr. of nitere to shine.]
   Brightness; luster. [R.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Nitency \Ni"ten*cy\, n. [From L. nitens, p. pr. of niti to
   strive.]
   Endeavor; effort; tendency. [R.] --Boyle.
   [1913 Webster] Niter