这个短语的字面解释是“公鸡和公牛的故事”，这是什么意思呢？请看对话：

    A: I asked for an explanation, and all I got was your ridiculous cock and bull story!

    B: Sorry if you don’t believe it, but I have told you the truth.

    Note: The idiom means a fabricated story meant to deceive and/or amuse. The Phrase Finder suggests the phrase came about when coaches would carry travelers to one of two inns that were close to each other on the old London Road at Stony Stratford near Buckinghamshire, England. Rivalries arose between the groups of travelers who favored one inn over the other, and boastful tales were exchanged. The names of the two inns? The Cock and the Bull, of course. There’s a French variation, coq-a-l’ane (cock to donkey), and a Scottish derivative of the French variation — “cockalayne.”