character trait
character trait (rasgo de carácter)
a lasting quality of a character's personality, such as honest, stubborn, generous or shy.
Example
Even when no one was watching, Tom returned the extra change. (Trait: honest.)
In Spanish
character trait (rasgo de carácter) — una cualidad duradera de la personalidad de un personaje, como honesto, terco, generoso o tímido.
Even when no one was watching, Tom returned the extra change. (Rasgo: honesto.)