Source : Webster's Revised Unabridged Dictionary (1913)

Pertinacity \Per`ti*nac"i*ty\, n. [Cf. F. pertinacit['e].]
   The quality or state of being pertinacious; obstinacy;
   perseverance; persistency. --Macaulay.

   Syn: See {Obstinacy}.

Source : WordNet®

pertinacity
     n : persistent determination [syn: {doggedness}, {perseverance},
          {persistence}, {persistency}, {tenacity}, {tenaciousness}]