The Collaborative International Dictionary of English v.0.48:

Nithing \Nith"ing\, n. [Obs.]
   See Niding.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Niding \Ni"ding\ (n[imac]"d[i^]ng), n. [Written also nithing.]
   [AS. n[imac][eth]ing, fr. n[imac][eth] wickedness, malice,
   hatred.]
   A coward; a dastard; -- a term of utmost opprobrium. [Obs.]
   [1913 Webster]

         He is worthy to be called a niding.      --Howell.
   [1913 Webster]