In UK in 1977 the Queen celebrated Silver Jubilee (1952 + 25)
An 150 year celebration is called a Sesquicentennial celebration
It is called a "centennial celebration"
A 100 year celebration is called a centennial celebration.
60 year celebration
An 150 year celebration is called a Sesquicentennial celebration
55th wedding celebration is Emerald.
Centennial
It is called Centenary.
Diamond Jubilee
An Emerald anniversary
It is a century or a centennial
Diamond Jubilee