as the crow flies
直线距离，不计较道路或障碍物的飞行距离
口语·地理·表示直线距离
英文释义
the shortest or most direct route between two points
例句
It's only five miles as the crow flies, but the winding road makes it ten.
典故来源
乌鸦飞行时通常走直线，不绕路，因此用来比喻两点之间的直线距离。