THESAURUS
trimester
abundant year, academic year, annum, bissextile year, calendar month, calendar year, century, clover, common year, day, decade, decennary, decennium, defective year, deuce-ace, fiscal year, fortnight, hour, leap year, leash, lunar month, lunar year, lunation, luster, lustrum, man-hour, microsecond, millennium, millisecond, minute, moment, month, moon, quarter, quinquennium, regular year, second, semester, session, set of three, shamrock, sidereal year, solar year, sun, tercet, term, ternary, ternion, terzetto, three, threesome, tierce, trefoil, trey, triad, trialogue, triangle, tricorn, trident, triennium, trihedron, trilogy, trine, trinity, trinomial, trio, triphthong, triple crown, triple threat, triplet, triplopy, tripod, triptych, trireme, triseme, triskelion, trisul, triumvirate, triunity, trivet, troika, twelvemonth, week, weekday, year