Definition of "unseen"

You became to me the visible incarnation of that unseen ideal whose memory haunts us artists like an exquisite dream.

1891, Oscar Wilde, chapter 9, in The Picture of Dorian Gray, London, New York, N.Y., Melbourne, Vic.: Ward Lock & Co.

Were one asked to characterize the life of religion in the broadest and most general terms possible, one might say that it consists of the belief that there is an unseen order, and that our supreme good lies in harmoniously adjusting ourselves thereto.

1902, William James, The Varieties of Religious Experience, Lecture 3

Where we once sent love letters in a sealed envelope, or stuck photographs of our children in a family album, now such private material is despatched to servers and clouds operated by people we don't know and will never meet. Perhaps we assume that our name, address and search preferences will be viewed by some unseen pair of corporate eyes, probably not human, and don't mind that much.

2013 June 14, Jonathan Freedland, “Obama's once hip brand is now tainted”, in The Guardian Weekly, volume 189, number 1, page 18

I to the world am like a drop of waterThat in the ocean seeks another drop,Who, falling there to find his fellow forth,Unseen, inquisitive, confounds himself.

c. 1594 (date written), William Shakespeare, “The Comedie of Errors”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act I, scene ii]

The advent of COVID passports, so soon after increased check-in bureaucracy post-Brexit, brought major logistical ramifications to St Pancras International, of a kind unseen at any other major station in Britain.

2022 November 30, Nick Brodrick, “Pride and innovation shine at St Pancras”, in RAIL, number 971, page 67