Treatise
Pronunciation : Trea"tise
Part of Speech : n.
Etymology : [OE. tretis, OF. treitis, traitis, well made. See Treat.]
Definition : 1. A written composition on a particular subject, in which its principles are discussed or explained; a tract. Chaucer. He published a treatise in which he maintained that a marriage between a member of the Church of England and a dissenter was a nullity. Macaulay.
Note: A treatise implies more form and method than an essay, but may fall short of the fullness and completeness of a systematic exposition.
2. Story; discourse. [R.] Shak.
Source : Webster's Unabridged Dictionary, 1913