How to Say "dissertation" in Spanish
The most common Spanish word for “dissertation” is “tesis” — use 'tesis' for the final, often research-based, project required to obtain a university degree, especially at the undergraduate or master's level.
tesis
TEH-seesˈtesis

Examples
Tengo que terminar mi tesis para graduarme en junio.
I have to finish my thesis to graduate in June.
Ella pasó meses investigando en la biblioteca para su tesis doctoral.
She spent months researching in the library for her doctoral dissertation.
El jurado hizo preguntas muy difíciles durante la defensa de su tesis.
The jury asked very difficult questions during his thesis defense.
The 'Is' Rule
Even though it ends in 's,' this word is feminine. Always use 'la' or 'una' with it.
One word, many items
The word 'tesis' doesn't change when it becomes plural. To say 'theses,' you just change the word 'the' from 'la' to 'las'.
The Gender Trap
Mistake: “El tesis es muy larga.”
Correction: La tesis es muy larga. (Tesis is feminine, so you must use 'la' and match the adjective ending).
Adding extra 'es'
Mistake: “Tengo que leer muchas tesises.”
Correction: Tengo que leer muchas tesis. (Never add 'es' to the end of this word; it already sounds plural!)
memoria
meh-MOH-ree-ahmeˈmo.ɾja

Examples
El estudiante debe presentar una memoria de su proyecto final para graduarse.
The student must present a report of their final project in order to graduate.
La memoria anual de la empresa detalla todos los logros del año pasado.
The company's annual report details all the achievements of the past year.
Formal Context
This meaning is typically used in formal settings, like universities or business administration, referring to a specific document detailing research or results.
Tesis vs. Memoria
Related Translations
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