Jubilee

Etymology
See. The proper noun sense (“London Underground line”) was named after the silver jubilee of Queen of the United Kingdom (born 1926) in 1977.

Proper noun

 * 1)  A London Underground line which runs between Stratford in East London and Stanmore in northwest London, via the, South Bank, and West End.

Noun

 * 1)  (“(Jewish history) special year of emancipation supposed to be observed every fifty years; (Roman Catholicism) special year in which plenary indulgences and remission from sin can be granted”)