pessimist
US /ˈpes.ə.mɪst/
UK /ˈpes.ə.mɪst/

1.
pesimista
a person who tends to see the worst aspect of things or believe that the worst will happen
:
•
He's such a pessimist; he always expects things to go wrong.
Es un gran pesimista; siempre espera que las cosas salgan mal.
•
Don't listen to that old pessimist; things will work out.
No escuches a ese viejo pesimista; las cosas saldrán bien.