noun the·sis \ ˈthē-səs , British especially for sense 3 ˈthe-sis \
|Updated on: 20 Jul 2018

Definition of thesis

plural theses play \ˈthē-ˌsēz\
1 : a dissertation embodying results of original research and especially substantiating a specific view; especially : one written by a candidate for an academic degree
2 a : 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
3 a (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

Examples of thesis in a Sentence

  1. She wrote her thesis on Renaissance Nativity scenes.

  2. a master's thesis on the effects of global warming

  3. New evidence supports his thesis.

  4. We disagreed with the basic thesis of the report.

  5. The book's central thesis is that propaganda influences the masses in important ways.

Recent Examples of thesis from the Web

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.

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.

Origin and Etymology of 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

THESIS Defined for English Language Learners


Definition of thesis for English Language Learners

  • : 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

THESIS Defined for Kids


noun the·sis \ ˈthē-səs \

Definition of thesis for Students

plural theses \-ˌsēz\
1 : a statement that a person wants to discuss or prove
2 : an essay presenting results of original research

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to beat or defeat soundly

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