How to Say "to diagnose" in Spanish
The Spanish word for “to diagnose” is “diagnosticar” — B1 level.

Examples
El médico necesita más pruebas para diagnosticar la enfermedad.
The doctor needs more tests to diagnose the illness.
Es difícil diagnosticar el problema del coche sin abrir el motor.
It is difficult to identify the car's problem without opening the engine.
Los expertos diagnostican un cambio en el clima económico.
Experts identify a change in the economic climate.
The 'C' to 'QU' Spelling Change
In the past tense 'yo' form and all 'wishing' (subjunctive) forms, the 'c' changes to 'qu' to keep the hard 'k' sound: 'yo diagnostiqué' (I diagnosed).
Direct Action
Unlike English where we often use the passive ('He was diagnosed'), Spanish speakers often prefer the active voice: 'El médico lo diagnosticó' (The doctor diagnosed him).
Using 'con' incorrectly
Mistake: “El médico diagnosticó con gripe.”
Correction: El médico diagnosticó gripe.
Related Translations
Learn Spanish with Inklingo
Interactive stories, personalized learning, and more.