- next after the sixty-fifth; being the ordinal number for 66.
- being one of 66 equal parts.
- a sixty-sixth part, especially of one (1/66).
- the sixty-sixth member of a series.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for sixty-sixth
He died in London, July 26th, 1816, in the sixty-sixth year of his age.Lives of Illustrious Shoemakers
William Edward Winks
It was his sixty-sixth birthday, and it reminded him that he was behindhand with his great work.Walking Shadows
He was the sixty-sixth applicant Roger had seen that morning.The Space Pioneers
One day is a three hundred and sixty-fifth or a three hundred and sixty-sixth of a year.The Esperanto Teacher
So, the axe came down and struck his head off, in the sixty-sixth year of his age.A Child's History of England