| Noun | 1. | solar calendar - a calendar based on solar cycles calendar - a system of timekeeping that defines the beginning and length and divisions of the year Gregorian calendar, New Style calendar - the solar calendar now in general use, introduced by Gregory XIII in 1582 to correct an error in the Julian calendar by suppressing 10 days, making Oct 5 be called Oct 15, and providing that only centenary years divisible by 400 should be leap years; it was adopted by Great Britain and the American colonies in 1752 Julian calendar, Old Style calendar - the solar calendar introduced in Rome in 46 b.c. by Julius Caesar and slightly modified by Augustus, establishing the 12-month year of 365 days with each 4th year having 366 days and the months having 31 or 30 days except for February Revolutionary calendar - the calendar adopted by the first French Republic in 1793 and abandoned in 1805; dates were calculated from Sept. 22, 1792 |