Old Style calendar

Từ điển WordNet v3.1 - WordNet Dictionary

noun

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
• Syn:
Julian calendar
• Hypernyms:
solar calendar