How to Say "to reassure" in Spanish
The Spanish word for “to reassure” is “tranquilizar” — A2 level. This is a very common word in everyday Spanish.

Examples
La madre intenta tranquilizar al bebé que llora.
The mother is trying to calm the crying baby.
Tus palabras me tranquilizan mucho, gracias.
Your words reassure me a lot, thank you.
El médico habló con la familia para tranquilizarla antes de la cirugía.
The doctor spoke with the family to reassure them before the surgery.
The Spelling 'Z' to 'C' Swap
When a verb ends in '-zar', the 'z' changes to a 'c' whenever it is followed by an 'e'. This happens in the 'yo' form of the past (tranquilicé) and all present forms of the 'special wish/doubt' mood (tranquilice).
Using the 'Personal A'
Since you usually calm down a person (or a pet), you must use the word 'a' before the person you are calming. For example: 'Tranquilizo A mi hermana'.
Spelling Error in the Past
Mistake: “Yo tranquilizé”
Correction: Yo tranquilicé. In Spanish, we avoid writing 'ze' and use 'ce' instead.
Confusing 'Calm' with 'To Calm'
Mistake: “Estoy tranquilizar.”
Correction: Estoy tranquilo (I am calm) or Estoy tranquilizando a mi amigo (I am calming my friend). Use the adjective 'tranquilo' for descriptions and the verb for the action.
Related Translations
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