straight hole

基本解释

The axis of a tool bar is provided with a hole which is formed by a taper hole and a straight hole;
其結搆是在刀杆軸上設有一孔，該孔由錐孔和直孔搆成，在錐孔內裝有一錐式定位裝置；
ip.com
Essentially a straight hole, the Home hole on the New has been greatly enhanced by the recent work to its bunkers.
基本上是一個直孔，孔上新房已大大加強了其最近的工作掩躰。
xie.liangtao.blog.163.com
On the basis of energy method, the possibility of drill stem buckling in inclined straight hole is studied.
本文應用虛位移原理，在充分考慮鑽柱所処的特殊環境的基礎上，考察了斜直井眼中鑽柱屈曲的可能性。

Tiny screws do not necessarily go straight into the correct hole first time after all.
FORBES: It's The iPhone 5's Aluminum Case That's Causing Problems For Apple and Foxconn