An offer to use force to the injury of another is an assault, and the use of that force is a battery, which usually includes an assault. An assault and battery upon the person of another may be a criminal act. Courts generally hold, however, that a parent or one in loco parentis may inflict disciplinary corporal punishment upon a child without becoming criminally liable.
Norman D. Tripp, Acting In Loco Parentis as a Defense to Assault and Battery, 16 Clev.-Marshall L. Rev. 39 (1967)