quat·er·cen·te·na·ry /ˌkwætəsenˈtiːnəri $ ˌkwɑːtərsenˈten-/ noun (plural quatercentenaries) [countableC] TMthe day or year exactly 400 years after a particular event 四百周年纪念quatercentenary of the quatercentenary of Shakespeare’s birth 莎士比亚诞辰四百周年
Origin quatercentenary (1800-1900) Latin quater “four times” + English centenary