COCKED HAT, KNOCK (SOMETHING) INTO A

(slang) damage or spoil (something) completely; ruin or beat or defeat (something) completely. A cocked hat was a type of three-cornered hat worn in the 18th century. It was made by folding the edges of the round hat worn in the 17th century into corners. The phrase first meant to change something completely and later to defeat someone or something completely, and thus to damage, spoil or ruin. —Class VIII №10, Approved November 1990

(slang) damage or spoil (something) completely; ruin or beat or defeat (something) completely. A cocked hat was a type of three-cornered hat worn in the 18th century. It was made by folding the edges of the round hat worn in the 17th century into corners. The phrase first meant to change something completely and later to defeat someone or something completely, and thus to damage, spoil or ruin.