How to Say "to substantiate" in Spanish
The most common Spanish word for “to substantiate” is “comprobar” — use 'comprobar' when you need to formally verify or prove a fact, theory, or statement, often through evidence or testing.
comprobar
kom-proh-BARkom.pɾoˈβaɾ
Examples
El informe comprobó la eficacia del nuevo tratamiento.
The report substantiated the effectiveness of the new treatment.
El experimento comprobó la teoría del científico.
The experiment proved the scientist's theory.
La nueva evidencia comprueba su inocencia.
The new evidence proves his innocence.
No pudieron comprobar que el coche era robado.
They couldn't prove that the car was stolen.
Followed by 'que'
When 'comprobar' means 'to prove' or 'to confirm a fact,' it is usually followed by 'que' and the verb in the normal indicative (non-special) form: 'Comprobamos que está aquí.' (We confirmed that he is here.)
justificar
hoos-tee-fee-karxustifiˈkaɾ
Examples
Debes justificar tus compras con las facturas correspondientes.
You must substantiate your purchases with the corresponding invoices.
Debes justificar tus gastos de viaje con recibos.
You must account for your travel expenses with receipts.
Necesito un certificado médico para justificar mi falta.
I need a medical certificate to justify my absence.
No ha podido justificar el origen de su fortuna.
He hasn't been able to prove the source of his fortune.
Using 'con' for proof
To say what you are using to justify something, use 'con' (with). For example: 'Justifica los datos CON pruebas' (Justify the data with proof).
fundamentar
foon-dah-mehn-TAHRfunda-menˈtaɾ
Examples
El abogado fundamentó su defensa en pruebas sólidas.
The lawyer substantiated his defense with solid evidence.
Tienes que fundamentar tu respuesta con ejemplos claros.
You have to base your answer on clear examples.
El científico fundamentó su teoría en años de investigación.
The scientist grounded his theory in years of research.
La acusación no está bien fundamentada y fue rechazada por el juez.
The accusation is not well-substantiated and was rejected by the judge.
Using 'en' to show the base
Just like we say 'based on' in English, Spanish uses the word 'en' after fundamentar. For example: 'Fundamentar en la realidad' (To base on reality).
A regular -ar verb
Good news! This verb follows the normal pattern for verbs ending in -ar, like 'hablar' or 'cantar,' so you don't need to learn any weird spelling changes.
Confusing with 'Fundar'
Mistake: “Fundé mi opinión en el libro.”
Correction: Fundamenté mi opinión en el libro.
Proving vs. Backing Up
Related Translations
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