the·sis | \ ˈthē-səs , British especially for sense 3 ˈthe-sis \
plural theses\ˈthē-ˌsēz \

Definition of thesis 

1 : a dissertation embodying results of original research and especially substantiating a specific view especially : one written by a candidate for an academic degree

2a : a proposition to be proved or one advanced without proof : hypothesis

b : a position or proposition that a person (such as a candidate for scholastic honors) advances and offers to maintain by argument

3a(1) : the unstressed part of a poetic foot especially in accentual verse

(2) : the longer part of a poetic foot especially in quantitative verse

b : the accented part of a musical measure : downbeat — compare arsis

4 : the first and least adequate stage of dialectic — compare synthesis

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Did You Know?

In high school, college, or graduate school, students often have to write a thesis on a topic in their major field of study. In many fields, a final thesis is the biggest challenge involved in getting a master's degree, and the same is true for students studying for a Ph.D. (a Ph.D. thesis is often called a dissertation). But a thesis may also be an idea; so in the course of the paper the student may put forth several theses (notice the plural form) and attempt to prove them.

Examples of thesis in a Sentence

She wrote her thesis on Renaissance Nativity scenes. a master's thesis on the effects of global warming New evidence supports his thesis. We disagreed with the basic thesis of the report. The book's central thesis is that propaganda influences the masses in important ways.
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Recent Examples on the Web

Nick and his new wife, Eden (Sydney Sweeney), are joined together in holy matrimony to further the thesis of Gilead: making Gilead-worshipping babies, and saving humanity from a plague of infertility., "The Subversive Role Of Religion In The Handmaid's Tale," 16 May 2018 Distillate demand remained incredibly strong and supports a thesis for solid global petroleum demand. Stephanie Yang And Sarah Mcfarlane, WSJ, "Oil Prices Higher on Fed’s Economic Outlook," 2 May 2018 That’s where Bitcoin comes in—supporting his original thesis that Bitcoin will replace gold. Jen Wieczner, Fortune, "Why an Investor Is Predicting Bitcoin Could Hit $700,000," 25 Apr. 2018 The thesis of love always fights the antithesis of hate, but there is never a synthesis that joins the two. Carlos Valladares, San Francisco Chronicle, "Waking up to the genius of ‘The Night of the Hunter,’ showing at the Stanford," 23 Apr. 2018 At first blush, real estate technology doesn’t seem to fit Son’s stated thesis of a future dominated by artificial intelligence, robots, and big data. Erin Griffith, WIRED, "SoftBank's Futuristic Vision Fund Takes on the Real (Estate) World," 16 Apr. 2018 The research must support their final design thesis. Bonnie L. Cook,, "John Christopher Knowles, 79, founded and led Temple's architecture program," 29 Mar. 2018 The 2003 thesis was presented to an academy affiliated with the F.S.B., Russia’s domestic intelligence agency, that studies cryptography. Andrew E. Kramer, New York Times, "G.R.U., Russian Spy Agency Cited by Mueller, Casts a Long Shadow," 13 July 2018 Now, including Ryan Gravel, whose master’s thesis formed the basis of the necklace of trails and planned transit connecting 45 city neighborhoods, say the More MARTA tax is the vehicle to fulfill promises to build Beltline light rail. J. Scott Trubey, ajc, "Atlanta Beltline group pushes MARTA for funding of full rail loop," 12 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thesis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of thesis

14th century, in the meaning defined at sense 3a(1)

History and Etymology for thesis

in sense 3, Middle English, lowering of the voice, from Late Latin & Greek; Late Latin, from Greek, downbeat, more important part of a foot, literally, act of laying down; in other senses, Latin, from Greek, literally, act of laying down, from tithenai to put, lay down — more at do

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Statistics for thesis

Last Updated

14 Sep 2018

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Time Traveler for thesis

The first known use of thesis was in the 14th century

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More Definitions for thesis



English Language Learners Definition of thesis

: a long piece of writing on a particular subject that is done to earn a degree at a university

: a statement that someone wants to discuss or prove


the·sis | \ ˈthē-səs \
plural theses\-ˌsēz \

Kids Definition of thesis

1 : a statement that a person wants to discuss or prove

2 : an essay presenting results of original research

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Comments on thesis

What made you want to look up thesis? Please tell us where you read or heard it (including the quote, if possible).


alleviating pain or harshness

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