Concept
Regnal year
Related concepts (10)
Gregorian calendar
The Gregorian calendar is the calendar used in most parts of the world. It went into effect in October 1582 following the papal bull Inter gravissimas issued by Pope Gregory XIII, which introduced it as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years differently so as to make the average calendar year 365.2425 days long, more closely approximating the 365.2422-day 'tropical' or 'solar' year that is determined by the Earth's revolution around the Sun.
Japanese calendar
Japanese calendar types have included a range of official and unofficial systems. At present, Japan uses the Gregorian calendar together with year designations stating the year of the reign of the current Emperor. The written form starts with the year, then the month and finally the day, coinciding with the ISO 8601 standard. For example, February 16, 2003, can be written as either 2003年2月16日 or 平成15年2月16日 (the latter following the regnal year system).
Epoch
In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by congruity, or by following conventions understood from the epoch in question. The epoch moment or date is usually defined from a specific, clear event of change, an epoch event. In a more gradual change, a deciding moment is chosen when the epoch criterion was reached.
Japanese era name
The Japanese era name, also known as gengō, is the first of the two elements that identify years in the Japanese era calendar scheme. The second element is a number which indicates the year number within the era (with the first year being "gan"), followed by the literal "nen" meaning "year". Era names originated in 140 BCE in China, during the reign of the Emperor Wu of Han. As elsewhere in East Asia, the use of era names was originally derived from Chinese imperial practice, although the Japanese system is independent of the Chinese, Korean, and Vietnamese era-naming systems.
Anno Domini
The terms anno Domini (AD) and before Christ (BC) are used to label or number years in the Julian and Gregorian calendars. The term anno Domini is Medieval Latin and means "in the year of the Lord" but is often presented using "our Lord" instead of "the Lord", taken from the full original phrase "anno Domini nostri Jesu Christi", which translates to "in the year of our Lord Jesus Christ". The form "BC" is specific to English, and equivalent abbreviations are used in other languages: the Latin form, rarely used in English, is Ante Christum natum (ACN) or Ante Christum (AC).
Common Era
Common Era (CE) and Before the Common Era (BCE) are year notations for the Gregorian calendar (and its predecessor, the Julian calendar), the world's most widely used calendar era. Common Era and Before the Common Era are alternatives to the original Anno Domini (AD) and Before Christ (BC) notations used for the same calendar era. The two notation systems are numerically equivalent: " CE" and "AD " each describe the current year; "400 BCE" and "400 BC" are the same year.
Calendar
A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single and specific day within such a system. A calendar is also a physical record (often paper) of such a system. A calendar can also mean a list of planned events, such as a court calendar or a partly or fully chronological list of documents, such as a calendar of wills. Periods in a calendar (such as years and months) are usually, though not necessarily, synchronized with the cycle of the sun or the moon.
Shōwa era
The Shōwa era, ɕoːwadʑidai was the period of Japanese history corresponding to the reign of Emperor Shōwa (commonly known in English as Emperor Hirohito) from December 25, 1926, until his death on January 7, 1989. It was preceded by the Taishō era and succeeded by the Heisei era. The pre-1945 and post-war Shōwa periods are almost completely different states: the pre-1945 Shōwa era (1926–1945) concerns the Empire of Japan, and post-1945 Shōwa era (1945–1989) concerns the State of Japan.
Calendar era
A calendar era is the period of time elapsed since one epoch of a calendar and, if it exists, before the next one. For example, it is the year as per the Gregorian calendar, which numbers its years in the Western Christian era (the Coptic Orthodox and Ethiopian Orthodox churches have their own Christian eras). In antiquity, regnal years were counted from the accession of a monarch. This makes the chronology of the ancient Near East very difficult to reconstruct, based on disparate and scattered king lists, such as the Sumerian King List and the Babylonian Canon of Kings.
Julian calendar
The Julian calendar is a solar calendar of 365 days in every year with an additional leap day every fourth year (without exception). The Julian calendar is still used in parts of the Eastern Orthodox Church and in parts of Oriental Orthodoxy as well as by the Berbers, whereas the Gregorian calendar is used in most parts of the world. This calendar, proposed by Roman consul Julius Caesar in 46 BC, was a reform of the earlier Roman calendar, a largely lunisolar one. It took effect on 1 January 45 BC, by edict.