1. to lack confidence in one's abilities, decisions, or worth; to question oneself
She has self-doubt about whether she can succeed in the new job.
Ela tem dúvidas sobre si mesma sobre se conseguirá ter sucesso no novo trabalho.
2. to experience uncertainty or lack of faith in one's own capabilities
Many students have self-doubt before important exams.
Muitos estudantes têm dúvidas sobre si mesmos antes de exames importantes.