1907, w, The Dust of Conflict Chapter 6, The night was considerably clearer than anybody on board her desired when the schooner Ventura headed for the land. It rose in places, black and sharp against the velvety indigo, over her dipping bow, though most of the low littoral was wrapped in obscurity.
1919, William Somerset Maugham, The Moon and Sixpence,I walked in, and Stroeve followed me. The room was in darkness. I could only see that it was an attic, with a sloping roof; and a faint glimmer, no more than a less profound obscurity, came from a skylight.
The state of being unknown; a thing that is unknown.
1922, Ben Travers, A Cuckoo in the Nest Chapter 5, The departure was not unduly prolonged....Within the door Mrs. Spoker hastily imparted to Mrs. Love a few final sentiments...; a deep, guttural instigation to the horse; and the wheels of the waggonette crunched heavily away into obscurity.
The quality of being difficult to understand; a thing that is difficult to understand.