means A hollow space, gap, or opening in or through something solid.

from From Old English 'hol,' meaning a hollow place or cavity, and rooted in a Proto-Germanic word also tied to 'hollow' itself — the two are close kin. The deeper Indo-European root carried the sense of covering or concealing, the idea of something tucked away in a hidden recess. So a hole began life less as 'a gap' and more as 'a place that hides.'