Platinum jubilee
A platinum jubilee is a celebration held to mark an anniversary. Among monarchies, it usually refers to a 70th or 75th anniversary. For example, in 2016, King Bhumibol of Thailand could celebrate his platinum jubilee at the age of 88 years and 188 days. Another example is Queen Elizabeth II, who could celebrate her platinum jubilee in 2022 (at the age of 95 years and 292 days old) in the United Kingdom and the rest of the Commonwealth realms.
In South Asian usage, a "platinum jubilee" refers not to an anniversary, but the celebration of 75 weeks. For instance, in Pakistan and India, a platinum jubilee film is one shown in cinemas for 75 weeks or more. The success measure for a 'super hit film' is minimum six months release on its main cinema.
The term is uncommon in the United States, where a 75th anniversary is termed a "diamond jubilee" (in reference to an event only).
The next level of celebration, an anniversary of 100 years, is simply called a centenary.
See also
Silver jubilee