Source : Webster's Revised Unabridged Dictionary (1913)

Taciturnity \Tac`i*tur"ni*ty\, n. [L. taciturnitas: cf. F.
   taciturnit['e].]
   Habilual silence, or reserve in speaking.

         The cause of Addison's taciturnity was a natural
         diffidence in the company of strangers.  --V. Knox.

         The taciturnity and the short answers which gave so
         much offense.                            --Macaulay.

Source : WordNet®

taciturnity
     n : the trait of being uncommunicative; not volunteering
         anything more than necessary [syn: {reserve}, {reticence}]