Source : Webster's Revised Unabridged Dictionary (1913)

Calendric \Ca*len"dric\, Calendrical \Ca*len"dric*al\, a.,
   Of or pertaining to a calendar.

Source : WordNet®

calendric
     adj : relating to or characteristic of or used in a calendar or
           time measurement; "calendric systems"; "solstice is a
           time of calendric importance" [syn: {calendrical}]