un fallo

mistake; fault; failure

→ uno
phrase Rare #33,268
mistake; fault; failure Used for an error, a defect, or something not working properly, depending on context.
SP: Hubo un fallo en la conexión y no pudimos terminar la llamada.
EN: There was a connection problem and we couldn't finish the call.

Dicen que es un fallo del cerebro.

They say it's a problem with the brain.

— Open Your Eyes (1997)

Estábamos grabando la escena cuando se cortó el sonido por un fallo técnico.

We were recording the scene when the sound cut out due to a technical failure.

Un fallo y mueres.

One mistake and you're dead.

— Scream 7 (2026)

La tormenta provocó un fallo y no hay luz.

The storm caused a power outage and there is no electricity.

— Durante la tormenta (2018)

Hay un fallo en el sistema eléctrico.

There is a fault in the electrical system.

En caso de un fallo total lo que tenéis que hacer es esto.

In the event of a total failure, this is what you need to do.

— Sólo se vive una vez (2011)

He puesto un fallo y no lo era.

I marked it as an error, but it wasn't one.

— Las diabólicas (1955)

A veces incluso un genio comete un fallo.

Sometimes even a genius makes a mistake.