(n.) A period of six months; especially, a term in a college or university which divides the year into two terms.

abundant year academic year annum bissextile year calendar month calendar year century common year day decade decennary decennium defective year fiscal year fortnight hour leap year lunar month lunar year lunation luster lustrum man-hour microsecond millennium millisecond minute moment month moon quarter quinquennium regular year second session sidereal year solar year sun term trimester twelvemonth week weekday year