Culpable (klp-b'l), a.
Etymology: [OE. culpable, coulpable, coupable, F. coupable, formerly also coupable, formerly also coulpable, culpable, fr. L. culpabilis, fr. culpare to blame, fr. culpa fault.]
1. Deserving censure; worthy of blame; faulty; immoral; criminal. State Trials (1413). If he acts according to the best reason he hath, he is not culpable, though he be mistaken in his measures. Sharp.
2. Guilty; as, clpable of a crime. [Obs.] Spenser. -- Cul"pa*ble*ness, n. -- Cul"pa*bly, adv.
Shades of meaning
Fernald has no entry of its own for culpable; he lists it under criminal.
He lists it without comment; the entries above explain its neighbors.