← BackshareGuessbrainsick/ˈbreɪnˌsɪk/adjectiveMentally ill or insane; having a disordered mind.She was not brainsick, just deeply troubled by the events of her past.The old king was considered brainsick and unfit to rule.In the novel, the protagonist's brainsick behavior alarms his family.SynonymslunaticinsanederangedAntonymssane