Disillusioned/ˌdɪsɪˈluːʒnd/ Definition 1 of 1Pro Tip 1/3Lost Belief Emphasizes a strong sense of disappointment from finding out a belief is not true. He became disillusioned with his hero after the scandal. Pro Tip 2/3Emotional Impact Conveys deep emotional letdown, not just casual disappointment. Disillusioned by the academic world, she left her research job. Pro Tip 3/3Cultural Context Often used to describe a reaction to societal or systemic issues. After witnessing constant inequality, he felt disillusioned with society.