A hole in your eye! (5)

I believe the answer is:

pupil

I'm a little stuck... Click here to teach me more about this clue!

'a hole' is the definition.
(I know that pupil is a type of aperture)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for pupil that I've seen before include "Scholar" , "Learner in the eye?" , "that shrinks from brightness" , "part of my anatomy" , "feature in "Observer"?" .)

I've seen this clue in the Evening Standard.

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