Source : Webster's Revised Unabridged Dictionary (1913)

Punctuality \Punc`tu*al"i*ty\, n. [Cf. F. ponctualit['e].]
   The quality or state of being punctual; especially, adherence
   to the exact time of an engagement; exactness.

Source : WordNet®

punctuality
     n : the quality or habit of adhering to an appointed time [syn:
         {promptness}] [ant: {tardiness}]