English year (via
West Saxon ġēar (jɛar),
Anglian ġēr) continues
Proto-Germanic *jǣran (*j
ē₁ran). Cognates are
Old High German jār,
Old Norse ár and
jer, from the
Reconstruction:Proto-Indo-European/yeh₁-|*yeh₁r-om "year, season". Cognates also descended from the same Proto-Indo-European noun (with variation in suffix
Avestan yārǝ "year",
Greek ὥρα (hṓra) "year, season, period of time" (whence "
Old Church Slavonic jarŭ, and
Latin hornus "of this year".
2nd declension masculine noun; annum is the
accusative singular; annī is genitive singular and nominative plural; annō 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).
Both *yeh₁-ro- and *h₂et-no- are based on verbal roots expressing movement, *h₁ey- and *h₂et- respectively, both meaning "to go" generally (compare
Vedic Sanskrit éti "goes", atasi "thou goest, wanderest"). Derived from Latin annus are a number of English words, such as
per annum means "each year",
anno Domini 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
Sanskrit vat-sa-ras "year" and vat-sa- "yearling (calf)", the latter also reflected in Latin
vitulus "bull calf", English wether "ram" (Old English weðer, Gothic wiþrus "lamb").
In some languages, it is common to count years by referencing to one season, as in "summers", or "winters", or "harvests". Examples include Chinese
年 "year", originally
秂, an ideographic compound of a person carrying a bundle of wheat denoting "harvest". Slavic besides
godŭ "time period; year" uses
lěto "summer; year".