1. The system according to which the beginning and length of successive civil years, and the subdivision of the year into its parts, is fixed; as the Babylonian, Jewish, Roman, or Arabic calendar.
   Julian Calendar, that introduced by Julius Caesar b.c. 46, in which the ordinary year has 365 days, and every fourth year is a leap year of 366 days, the months having the names, order, and length still retained.
   Gregorian Calendar, the modification of the preceding adapted to bring it into closer conformity with astronomical data and the natural course of the seasons, and to rectify the error already contracted by its use, introduced by Pope Gregory XIII in a.d. 1582, and adopted in Great Britain in 1752. See style.

   2. A table showing the division of a given year into its months and days, and referring the days of each month to the days of the week; often also including important astronomical data, and indicating ecclesiastical or other festivals, and other events belonging to individual days. Sometimes containing only facts and dates belonging to a particular profession or pursuit, as Gardener's Calendar, Racing Calendar, etc. Also a series of tables, giving these facts more fully; an almanac.

   b. A contrivance for reckoning days, months, etc.

   †3. fig. A guide, directory: an example, model.

   4. A list or register of any kind. (In the general sense, now only fig.)

   b. esp. A list of canonized saints, or the like. (Now usually treated as a form of sense 2, the days dedicated to the memory of the saints being usually registered in the ‘calendar’ or almanac.)

   c. A list of prisoners for trial at the assizes.

   d. spec. A list or register of documents arranged chronologically with a short summary of the contents of each, so as to serve as an index to the documents of a given period.

   †5. fig. A record. Obs.

   †b. An outward sign, index. Obs.

   †6. One who has charge of records or historical documents. Occurring in the name of an ancient guild in Bristol. Obs.

   7. attrib. and Comb., as calendar-day, -holiday, -saint; calendar-clock, a clock which indicates the days of the week or month; calendar-court, a court of justice held on a day appointed in the calendar; calendar month, one of the twelve months into which the year is divided according to the calendar; also the space of time from any day of any such month to the corresponding day of the next, as opposed to a lunar month of four weeks.