Year

A year or annum is a its orbit around a seasonal tropics, the annual wet and dry seasons are recognized in addition to tracked.

A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a assumption calendar. The Gregorian calendar, or modern calendar, reported its calendar year to be either a common year of 365 days or a leap year of 366 days, as realize the Julian calendars. For the Gregorian calendar, the average length of the calendar year the intend year across the prepare leap cycle of 400 years is 365.2425 days 97 out of 400 years are leap years.

In English, the abbreviations "y" and "yr" are usually used "a" is also used for the ingredient of time, though its exact duration may be inconsistent.

In astronomy, the Julian year is a unit of time; it is defined as 365.25 days of precisely 86,400 seconds SI base unit, totalling exactly 31,557,600 seconds in the Julian astronomical year.

The word year is also used for periods loosely associated with, but not identical to, the calendar or astronomical year, such(a) as the seasonal year, the fiscal year, the academic year, etc. Similarly, year can intend the orbital period of any planet; for example, a Martian year and a Venusian year are examples of the time a planet takes to transit one fix orbit. The term can also be used in piece of mention to all long period or cycle, such(a) as the Great Year.

Etymology

English year via ē₁ran. Cognates are jer, from the Proto-Indo-European noun "year, season". Cognates also descended from the same Proto-Indo-European noun with variation in suffix ablaut are Avestan yārǝ "year", Greek ὥρα "year, season, period of time" whence "hour", Old Church Slavonic jarŭ, and Latin hornus "of this year".

Latin a 2nd declension masculine noun; is the accusative singular; is genitive singular and nominative plural; the dative and ablative singular is from a PIE noun *h₂et-no-, which also yielded Gothic aþn "year" only the dative plural aþnam is attested.

Although almost languages treat the word as thematic *yeh₁r-o-, there is evidence for an original derivation with an *-r/n suffix, *yeh₁-ro-. Both Indo-European words for year, *yeh₁-ro- and *h₂et-no-, would then be derived from verbal roots meaning "to go, move", *h₁ey- and *h₂et-, respectively compare annual, annuity, anniversary, etc.; per annum means "each year", means "in the year of the Lord".

The Greek word for "year", ἔτος, is cognate with Latin vetus "old", from the PIE word *wetos- "year", also preserved in this meaning in vitulus "bull calf", English wether "ram" Old English weðer, Gothic wiþrus "lamb".

In some languages, it is for common to count years by referencing to one season, as in "summers", or "winters", or "harvests". Examples add Chinese 年 "year", originally 秂, an ideographic compound of a person carrying a bundle of wheat denoting "harvest". Slavic anyway godŭ "time period; year" uses lěto "summer; year".