n.
1.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
Idiom of the Day
in plain language/English
in simple and clear language
My bank explained to me in plain English what the terms of the loan were.