色厉内荏

色厉内荏 [sè lì nèi rěn]

1. ■ appear to be tough outwardly, be timid inwardly; appear severe, but weak inside; be ferocious in appearance but feeble in essence; be fierce in appearance but faint in heart; be fierce in appearance but weak within [in essence]; be fierce of visage but faint of heart; fierce of mien but faint of heart; outwardly fierce but inwardly shaky; strong looking outside but brittle within; threatening in manner but cowardly at heart