Lewis & Short

ac-crēdo (adc.), dĭdi, dĭtum, 3, v. a. (pres. sub. adcredŭas, Plaut. Asin. 5, 2, 4), to yield one’s belief to another, i. e. to believe unconditionally (rare).

        1. (α) With dat.: quisnam istuc adcredat tibi? Plaut. Asin. 3, 3, 37: neque mi posthac quidquam adcreduas, id. ib. 5, 2, 4; so, tibi nos, Hor. Ep. 1, 15, 25.
        2. (β) Aliquid: facile hoc, Lucr. 3, 856.
        3. (γ) Absol.: vix adcredens, * Cic. Att. 6, 2, 3: primo non accredidit, Nep. Dat. 3. 4.