treatise

Etymology

From Middle English tretys, from Anglo-Norman tretiz and Old French traitis (“treatise, account”), from traitier (“to deal with, treat”).

noun

1. A formal, usually lengthy, systematic discourse on some subject.
   And if someone wants to know how to make objections to actual craftsmen themselves on the subject of art in general or any particular art, there are published treatises available, as you know. 2005, Plato, translated by Lesley Brown, Sophist, page 232d
   Some poems, echoing the purpose of early poetic treatises on scientific principles, attempt to elucidate the mathematical concepts that underlie prime numbers. Others play with primes’ cultural associations. Still others derive their structure from mathematical patterns involving primes. 2013 July-August, Sarah Glaz, “Ode to Prime Numbers”, in American Scientist, volume 101, number 4