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Synonyms

treatise

American  
[tree-tis] / ˈtri tɪs /

noun

  1. a formal and systematic exposition in writing of the principles of a subject, generally longer and more detailed than an essay.

treatise British  
/ ˈtriːtɪz /

noun

  1. a formal work on a subject, esp one that deals systematically with its principles and conclusions

  2. an obsolete word for narrative

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of treatise

1300–50; Middle English tretis < Anglo-French tretiz, akin to Old French traitier to treat

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Reading Mr. Emanuel’s treatise reminded me of a conference we had with our son’s fourth-grade teacher in the early 1970s.

From The Wall Street Journal • Jan. 26, 2026

The book jacket features a prominent blurb from Johnson calling the doctor’s treatise: “A gripping tale of corruption and courage that will open eyes and prompt serious questions.”

From Salon • Dec. 15, 2025

Johann Fischer's 1852 treatise on lizard neuroanatomy included part of the coil but omitted the remainder, and Fischer never described the curled structure.

From Science Daily • Nov. 19, 2025

Evans told reporters he would not describe the notebook found in the car as a "manifesto" as it was not "a treatise on all kinds of ideology and writings".

From BBC • Jun. 16, 2025

Enstice's conclusion was further discredited by Dr. Werner Spitz, who had authored the medical treatise Enstice had relied on in her forensic pathology training.

From "Just Mercy" by Bryan Stevenson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.