Definition of "oddity"

In the old days, to my commonplace and unobserving mind, he gave no evidences of genius whatsoever. He never read me any of his manuscripts, […], and therefore my lack of detection of his promise may in some degree be pardoned. But he had then none of the oddities and mannerisms which I hold to be inseparable from genius, and which struck my attention in after days when I came in contact with the Celebrity.

1897 December (indicated as 1898), Winston Churchill, chapter I, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd., page 1

An Avonside 0-4-4T with outside cylinders, bought by the S.M.A. in 1882 and scrapped in 1892 as a dismal failure, was one of the motive power oddities (some of them mortgaged).

1961 October, “Talking of Trains: Last of the M.S.W.J.R.”, in Trains Illustrated, page 586

Fête succeeded fête in honour of the arrival of Christina of Sweden, who seemed to communicate her own reckless love of novelty to the then somewhat staid French court. Claim your privileges as an oddity, and even you yourself will be astonished at their extent.

1834, L[etitia] E[lizabeth] L[andon], Francesca Carrara. […], volume I, London: Richard Bentley, […], (successor to Henry Colburn), pages 207–208

The thing was unprecedented in his experience, and probably he wondered in his equine way at the eccentricities of the human race, and questioned whether oddity might not be merging into insanity in his master’s case.

1869, E[llen] L. B[iscoe Hollis], “Mr. Wilmington’s Opposition”, in Katharine’s Experience, Boston, Mass.: […] Warren and Blakeslee, […], page 311