Source : Webster's Revised Unabridged Dictionary (1913)

Brevity \Brev"i*ty\, n.; pl. {Brevities}. [L. brevitas, fr.
   brevis short: cf. F. bri[`e]vit['e]. See {Brief}.]
   1. Shortness of duration; briefness of time; as, the brevity
      of human life.

   2. Contraction into few words; conciseness.

            Brevity is the soul of wit.           --Shak.

            This argument is stated by St. John with his usual
            elegant brevity and simplicity.       --Bp. Porteus.

   Syn: Shortness; conciseness; succinctness; terseness.

Source : WordNet®

brevity
     n 1: the use of brief expressions
     2: the attribute of being brief or fleeting [syn: {briefness},
        {transience}]