Nowadays, “cobblers” means that something is unbelievable or nonsense – codswallop. The phrase originates with cockney rhyming slang. It comes from the rhyming of a phrase with “a load of balls”, a phrase current in England for centuries. A cobbler's awl is a tool used to make holes for laces in shoes or boots. In rhyming slang, “balls” became “cobblers awls”, or cobblers.