Preposition: of

• second: There are 30 frames per second meaning that current screens only show half the frame every sixtieth of a second.

• degree: Research by the BBC confirmed that the correct figure for 20/20 visual acuity is a sixtieth of a degree.

Modifies a noun

• anniversary: The D Day landings June 6 2004 saw the sixtieth anniversary of the allied invasion of Normandy.

• birthday: Ruth also brought a cake for her sixtieth birthday which set the scene for a healthy eating weekend, not!

• session: He remained confident that the Committee would be able to complete its work before the end of the Assembly's sixtieth session.

• year: A dinner to celebrate the school's sixtieth year was held in the school hall on Saturday, 2nd October, 1965.

• minute: The second half did not spring into life until the sixtieth minute.