Lewis & Short

intrĕpĭdans, antis, adj. [2. in-trepido], not shaking, firm, strong, powerful (post-class.), Inscr. ap. Paulovich. Marm. Macarens. p. 61.
Adv.: intrĕpĭdan-ter, without trembling, intrepidly: ascendere, Non. 530, 5.