(idiomatic) A reprimand or rarely, a thrashing.
Example: "I'll give him a dressing down, see if I don't." Mrs. Mudge's eyes snapped viciously, and she clutched the relics of the broom with a degree of energy which rendered it uncertain what sort of a dressing down she intended for her husband. â€” Horatio Alger, Jr., "Paul Prescott's Charge", 1865
When the blacksmith saw what Babo had done to his mother, he caught him by the collar, and fell to giving him such a dressing down as never man had before. â€” Howard Pyle, "Twilight Land", 1894
"We must all bow to you, and try to get a favorable word, must we? This man shall have a leg up, and this man shall have a dressing down!" â€” A. Conan Doyle, "The Lost World", 1912