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Synonyms

treatise

American  
[tree-tis] / ˈtri tɪs /

noun

treatises plural
  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

Other Word Forms

Noun Inflected Forms

Etymology

Origin of treatise

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

Explanation

A treatise is a formal written paper about a specific subject. It’s like an essay but longer. A treatise is usually about a serious subject, so you might read a treatise on democracy, but you probably won't read a treatise about chewing gum. The word treatise is related to the verb treat, in the sense of "deal with,” like the way a doctor treats a patient. Like a doctor, a treatise examines a subject from all angles. It has nothing to do with treats, unless you’re writing a treatise on desserts, which would be weird. More appropriate topics for a treatise include philosophy, religion, economics, and so forth. An example of a political treatise is The Prince by Machiavelli, which basically argues that “the ends justify the means.”

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Vocabulary lists containing treatise

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

Too much time spent on Marty’s mother or his fierce opponent would distract from the film’s momentum, reducing it to simply a sports movie, and not a conclusive treatise on the cruelty of desire.

From Salon • Dec. 25, 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

Through it all, he continued to read deeply in philosophy, mathematics, and physics as he worked on a sprawling treatise he calls the “CTMU”—the “Cognitive Theoretic Model of the Universe.”

From "Outliers" by Malcolm Gladwell

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