year

n.
1 (also astronomical year, equinoctial year, natural year, solar year, tropical year) the time occupied by the earth in one revolution round the sun, 365 days, 5 hours, 48 minutes, and 46 seconds in length (cf. sidereal year).
2 (also calendar year, civil year) the period of 365 days (common year) or 366 days (see leap year) from 1 Jan. to 31 Dec., used for reckoning time in ordinary affairs.
3 a a period of the same length as this starting at any point (four years ago). b such a period in terms of a particular activity etc. occupying its duration (school year; tax year).
4 (in pl.) age or time of life (young for his years).
5 (usu. in pl.) colloq. a very long time (it took years to get served).
6 a group of students entering college etc. in the same academic year.
Phrases and idioms:
in the year of Our Lord (foll. by the year) in a specified year AD. of the year chosen as outstanding in a particular year (sportsman of the year). a year and a day the period specified in some legal matters to ensure the completion of a full year. the year dot see DOT(1). year in, year out continually over a period of years. year-long lasting a year or the whole year. year of grace the year AD. year-round existing etc. throughout the year.
Etymology: OE ge(a)r f. Gmc