Source : Webster's Revised Unabridged Dictionary (1913)

Pugnacity \Pug*nac"i*ty\, n. [L. pugnacitas: cf. F.
   pugnacit['e].]
   Inclination or readiness to fight; quarrelsomeness. `` A
   national pugnacity of character.'' --Motley.

Source : WordNet®

pugnacity
     n : a disposition to fight [syn: {aggressiveness}, {contentiousness},
          {belligerence}, {quarrelsomeness}]