涨知识：13个让你看不懂的英文习语的起源

A very close-up or right-on target is "point blank." It comes from the French "point blanc," and refers to the center of the target for shooting or archery practice.
一个闭合的或正中央的靶心就是“白点”（point blank），来自于法语point blanc，指代用来射击或射箭练习的靶子的中心。

"Point blanc" literally translates as a white point, and refers to the dead center of the target.
Point blanc字面上译作白点，指靶子的正中心。

The original meaning of "right on target" then evolved to mean something close up, making it easier to hit the middle of the target.
这个短语最初的意思“正中靶心”（right on target），就演变成某种闭合的圆圈的意思，这样的圆圈可使打中靶心变得更容易。