anniversary/ˌænɪ'vɜːsərɪ $ -'vɜːr-/

n. the date when you celebrate an event that happened on the same day in a previous year

n. 〖复-ries/-rɪz/〗 [C] 周年纪念日：their 10th wedding anniversary 他们的10周年结婚纪念日

◇[anniversary of sth] celebrate the 20th anniversary of the country's independence 庆祝该国独立20周年

◇an anniversary party/dinner 周年纪念派对/宴会

构词anni (= annual每年) + -vers- (转动) + -ary→每年都返回

同根 controversial; conversation; diverse; universe; university; version