cen ‧ te ‧ na ‧ ry /senˈtiːnəri $ -ˈten-, ˈsent ə neri/ BrE AmE noun ( plural centenaries ) especially British English ( also cen‧ten‧ni‧al /senˈteniəl/ especially American English ) [countable]
the day or year exactly 100 years after a particular event
centenary of
a concert to mark the centenary of the composer’s birth