Definition of "unique"

Perhaps the reader will wonder why we have placed our " beings " on a sphere rather than on another closed surface. But this choice has its justification in the fact that, of all closed surfaces, the sphere is unique in possessing the property that all points on it are equivalent.

1920, Robert W. Lawson, Relativity: The Special and General Theory, translation of original by Albert Einstein

3. Both were written and published with the same unique chorus structure;4. Both compositions were written and published with the same unique harmonic structure;

1941, Allen v. Walt Disney

‘[…] There's every Staffordshire crime-piece ever made in this cabinet, and that's unique. The Van Hoyer Museum in New York hasn't that very rare second version of Maria Marten's Red Barn over there, nor the little Frederick George Manning—he was the criminal Dickens saw hanged on the roof of the gaol in Horsemonger Lane, by the way—’

1963, Margery Allingham, chapter 3, in The China Governess‎

Admiralty Island contains unique resources of scientific interest which need protection to assure continued opportunities for study.

1978, Jimmy Carter, Proclamation 4611

A very interesting history of United Nations at war in Korea, done in an[sic] unique question and answer style.

1998, Paul M. Edwards, The Korean War: An Annotated Bibliography‎, Greenwood Press, page 114

GPS assigns a unique C/A code and a unique P code to each satellite.

2002, The American Practical Navigator

1999, Harry J. Cargas, Problems Unique to the Holocaust‎

And as I look back, it seems to me that we were fairly unique, the sixty of us, in that there wasn’t one good mixer in the bunch.

1950, J.D. Salinger, For Esmé—With Love and Squalor

The phoenix, the unique of birds.

a. 1859, Thomas De Quincey, Language

[…] uniques of the game, Sauron and Morgoth, are found on levels 99 and 100 of the dungeon respectively, […]

2020, John Harris, Exploring Roguelike Games