Simple Definition of treatise

from our Learner's Dictionary

treatise

noun

ˈtriːtəs

plural treatises

: a book, article, etc., that discusses a subject carefully and thoroughly

—often + on

a treatise on higher education

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“Treatise.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/treatise. Accessed 18 Jun. 2026.

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