Of which there are two in a year; semiannual; biyearly.

Twice in a year; semiannually.

Happening once every year. / Over the course of one year

Once a year. / Every year.

Something that is published once a year.

A year that is not a leap year.

A holiday in many countries to welcome the New Year of the Gregorian calendar on January 1.

A vow that one makes on New Year's Eve or New Year's Day for the coming year.

A period covering the first few days of a calendar year. / In particular, January 1 in the Julian and Gregorian calendar (New Year’s Day) and the days following.

(astronomy) A unit of length (abbreviation ly; equal to just under 10 trillion kilometres (10¹⁶ metres)) equal to the distance light travels in one Julian year; used to measure extremely large distances.