Festival you will shortly open getting closer (6)
I believe the answer is:
eyelid
'getting closer' is the definition.
I can't tell whether this definition defines the answer.
'festival you will shortly open' is the wordplay.
'festival' becomes 'eid' (Muslim festival).
'you' becomes 'ye' (historical version of 'you').
'will' becomes 'll' (contracted form, as in 'he'll' - 'he will').
'shortly' means to remove the last letter.
'open' is an insertion indicator (some letters open a gap in others).
'ye'+'ll'='yell'
'yell' with its last letter taken away is 'yel'.
'eid' enclosing 'yel' is 'EYELID'.
Can you help me to learn more?
(Other definitions for eyelid that I've seen before include "Covering for organ of sight" , "Protective cover" , "Where stye may occur" , "Fold of skin on the face" , "Blinking membrane" .)