A scholarly book or a treatise on a single subject or a group of related subjects, usually written by one person.
I had never given much thought to the role of darkness in ordinary human affairs until I read a monograph prepared by John Staudenmaier, a historian of technology and a Jesuit priest, for a recent conference at MIT. Cullen Murphy, "Hello Darkness", The Atlantic Monthly, March 1996, Volume 277, No. 3, [ pp. 22-24.]
Wikipedia foundation.