serious, severe
Soy una persona seria y responsable en mi trabajo.
I am a serious and responsible person at work.
The situation is very serious.
Hay que hacer una pregunta seria.
A serious question must be asked.
Es una cosa seria, acá lo llamamos Platón porque vive de la Academia.
It's a serious matter; here we call him Plato because he lives off the Academy.
— El secreto de sus ojos (2009)
She is a serious person.
Dicen que la cosa se está poniendo muy seria.
They say things are getting very serious.
— Pedro Páramo (2024)
Entramos a una conversación seria.
We entered into a serious conversation.