Wiktionary
n. (context engineering English) A hole that does not extend completely through the wall; a dead end hole.
Wikipedia
A blind hole refers to a hole that is reamed, drilled, or milled to a specified depth without breaking through to the other side of the workpiece. The etymology is that it is not possible to see through a blind hole. Other types of holes also include through holes, and clearance holes. In this instance blind may also refer to any feature that is taken to a specific depth. More specifically referring to internally threaded hole (tapped holes).
Usage examples of "blind hole".
In the blind hole of sex she waltzed like a trained mouse, her jaws unhinged like a snake's, her skin horripilating in barbed plumes.
I peered down the shaft to make sure, but it was still just a blind hole that disappeared into dirty dark at the end of the light from my head lamp.