A calendar is a system of organizing days for social, religious, commercial or administrative purposes.
Generally speaking, a calendar year begins on the New Year's Day of the given calendar system and ends on the day before the following New Year's Day, and thus consists of a whole number of days.
An ergograph is a graph that shows a relation between human activities, or agricultural/climate factors, and a seasonal year.
is a first baseman for the Tohoku Rakuten Golden Eagles.
A leap year (also known as an intercalary year or bissextile year) is a calendar year containing one additional day (or, in the case of lunisolar calendars, a month) added to keep the calendar year synchronized with the astronomical or seasonal year.
A year is the orbital period of the Earth moving in its orbit around the Sun.