semicentennial

[ sem-ee-sen-ten-ee-uhl, sem-ahy- ]

adjective

1. of or relating to a fiftieth anniversary.

noun

1. a fiftieth anniversary.
2. the celebration of this anniversary.

semicentennial

/ ˌsɛmɪsɛnˈtɛnɪəl /

adjective

1. prenominal of or relating to the 50th anniversary of some event
2. occurring once every 50 years

noun

1. a 50th anniversary

Word History and Origins

Origin of semicentennial¹

First recorded in 1855–60; semi- + centennial