It is called a 'quincentennial'
Quin= five.
Centennial= a period of 100 years.
Sestercentennial. It's on the wiki under Anniversary.
It is called a bicentennial.
tricentenary
A Tercentenary.
An 150 year celebration is called a Sesquicentennial celebration
It is called a "centennial celebration"
A 100 year celebration is called a centennial celebration.
Luck.
60 year celebration
An 150 year celebration is called a Sesquicentennial celebration
55th wedding celebration is Emerald.
Centennial
It is called Centenary.
An Emerald anniversary
Diamond Jubilee
It is a century or a centennial