Definitions for eyeholeˈaɪˌhoʊl
Random House Webster's College Dictionary
a circular opening for the insertion of a pin, hook, rope, etc.; eye.
Origin of eyehole:
The hole to which the viewer places his or her eye in a device such as a telescope.
The hole in a helmet, skull, etc. corresponding to the position of the eye.
a circular opening to recive a hook, cord, ring, or rope; an eyelet