What’s the plural of “thesis”?
A thesis is “a long piece of writing on a particular subject, especially one that is done for a higher college or university degree.” The plural of thesis is theses (pronounced thee-seez).
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She submitted her thesis on quantum mechanics.
She submitted her thesis on quantum mechanics.
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The professor supervised several theses this year.
The professor supervised several theses this year.
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He wrote two thesis during his studies.
He wrote two thesis during his studies.
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The students presented their thesises at the conference.
The students presented their thesises at the conference.
- Thesis is singular.
- The plural of thesis is theses (thee-seez).
Nouns that end in –sis
Many Greek-origin nouns ending in -sis form their plural by replacing -is with -es. Examples include analysis → analyses, crisis → crises, oasis → oases, synopsis → synopses, and thesis → theses.
| singular | plural |
|---|---|
| thesis | theses |
| analysis | analyses |
| crisis | crises |
| oasis | oases |
| synopsis | synopses |
For the plural of “thesis,” change the -is ending to -es: theses.
Examples of “thesis” and “theses” in sentences
| Sentences with “thesis” (singular) | Sentences with “theses” (plural) |
|---|---|
|
She is writing her thesis on climate change. His thesis was well received by the committee. The thesis must be submitted by the end of the semester. |
The university library stores all graduate theses. Several theses on linguistics were presented. The professor has supervised many theses over the years. |
Synonyms of thesis
- dissertation
- paper
- treatise
- essay
- argument
- proposition
Origin of the word thesis
Thesis comes from Greek θέσις (thésis), meaning “a proposition, a setting down, position, thesis,” from the root τίθημι (títhēmi), “I put, place, set.”
Worksheet: Greek nouns
Question 1 of 10
FAQs
Q: What is the plural of “thesis”?
A: The plural of “thesis” is theses. This follows the Greek pattern of changing -is to -es for the plural.
Q: How do you pronounce “theses”?
A: “Theses” is pronounced “thee-seez”.
Q: Is “thesises” ever correct?
A: No, “thesises” is not a correct plural form. The only accepted plural is “theses”.
Q: What are some related words?
A: Related words include “dissertation”, “paper”, “treatise”, “essay”, “argument”, and “proposition”.
Q: What is the origin of “thesis”?
A: “Thesis” comes from Greek, meaning “a proposition, a setting down, position, thesis.”
Citation: Yash, D. “What’s the Plural of Thesis?” Grammarflex. www.grammarflex.com/whats-the-plural-of-thesis/
Sources
- Definition of thesis.
