Chinese idiom · 成语
风马牛不相及
Meaning
To be completely unrelated; to have nothing to do with each other.
Character by character
Origin and story
Historical accountZuo Zhuan (左傳), Duke Xi’s fourth year, records Duke Huan of Qi leading allied troops against Cai and then advancing toward Chu. A Chu envoy challenges the invasion by stressing how far apart the two states are: one is in the north, the other in the south, beyond even the mingling of wandering horses and cattle. Why, then, has Qi entered Chu’s territory?
The phrase is part of a diplomatic claim that the states have no business interfering with each other. Traditional explanations of 风 concern animals roaming or pursuing mates, rather than an unrelated list of wind, horses, and oxen. The later idiom describes matters with no connection.
Sources and further reading
In everyday life
你的穿衣风格和工作能力风马牛不相及，没必要一起评价。
Your clothing style has nothing to do with your ability at work; there is no need to judge them together.
A firm way to reject an alleged connection between two things.