Aperture, hole (7)
I believe the answer is:
opening
This clue is a double definition.
'aperture' is the first definition.
(I've seen this before)
'hole' is the second definition.
(an opening is a hole or gap)
(Other definitions for opening that I've seen before include "break" , "Inauguration" , "(Official) start - gap" , "Vacancy" , "Window of opportunity" .)