the Mason-Dixon Line

剑桥词典

the border between the states of Maryland and Pennsylvania in the US, traditionally considered to mark the division between the north and south of the US
梅森-狄尅森線（美國馬裡蘭州和賓夕法尼亞州之間的分界線，也是傳統上認爲的美國北方各州和南方各州的分界線） 返回 the Mason-Dixon Line