Year

A year is the orbital period of the Earth moving around the Sun. In astronomy, the Julian year is a unit of time, defined as 365.25 days of 86400 SI seconds each. The years have a duration of 365 days, 5 hours, 48 minutes and 48 seconds approximately.

Old Testament
The OT uses the word, which means "revolution" of time. The OT calendar contained two different years: the sacred year, that began in the spring, in the month of Nisan, and the civil year that began in the fall, in the month of Tishri. To the israelites the months began with the new moon, but the first month of the year was fixed.

Roman period
The ancient Roman year was composed of twelve lunar months of 29 days or 30 days alternately, totaling 354 days. However a day was added to the sum resulting in an odd number of 355 days. Julius Caesar fixed the civil year in 46 BC to 365¼ days. The ordinary year consisted of 365 days divided into twelve months.