Alternative spelling of yearlong.

The year adopted by any nation for the computation of time.

(astronomy, historical) One complete precession of the equinox, approximately 25,765 years. / (astronomy, historical) Any real or imagined cycle with astronomical or astrological significance.

The time taken for the Earth to complete one revolution with respect to its apsides, usually defined as the time between perihelion passages.

(education) The annual period during which a student attends school, college or university.

(idiomatic) Old age.

(hydrology) The timespan between October 1 and September 30 of the next year, differing from the calendar year because part of the precipitation that falls in late autumn and winter accumulates as snow and does not drain until the following spring or summer.

plural of lunar year

(literary) The later years of one's life, especially after one has finished one's career.

plural of academic year